IPA Kelas 10 - Notasi Ilmiah & Angka Penting | GIA Academy

GIA Academy
14 Jul 202323:20

Summary

TLDRThis educational video from Gia Academy introduces scientific notation, a method to express very large or small numbers concisely. It explains how to convert numbers into this format, emphasizing the benefits for simplifying calculations and measurements. The video also delves into significant figures, their importance in scientific measurements, and rounding rules. It concludes with practical examples and exercises to solidify understanding, aiming to enhance viewers' comprehension of these fundamental scientific concepts.

Takeaways

  • 😀 Scientific notation is a method of writing numbers in the form of a base number multiplied by a power of 10, making it easier to express very large or very small numbers.
  • 📚 The base number 'a' in scientific notation should be a real number between 1 and 10, and 'n' is an integer exponent, which can be positive or negative.
  • 🔍 To express very small numbers like the mass of an electron, you shift the decimal point to the right until the base number is between 1 and 10, resulting in a negative exponent.
  • 🌍 For very large numbers, like the mass of Jupiter, you add a decimal point after the last non-zero digit and shift it to the left until the base number is between 1 and 10, resulting in a positive exponent.
  • 📝 Scientific notation simplifies the writing of significant figures from measurements, facilitates algebraic calculations, and makes it easier to determine the order of magnitude of the measured quantities.
  • 📐 Significant figures include both certain and uncertain digits, where the last digit is the uncertain digit, representing the precision of the measuring instrument.
  • 🔢 The rules for determining the number of significant figures include counting all non-zero digits, zeros between non-zero digits, and zeros to the right of the decimal point if they follow a non-zero digit.
  • ✂️ Rounding rules for significant figures involve rounding up if the first uncertain digit is 5 or more, and rounding down if it is less than 5, with special consideration for numbers exactly at 5.
  • 🧩 In mathematical operations, the number of significant figures in the result should match the smallest number of significant figures among the numbers involved in the operation.
  • 🔢 The difference between approximate numbers, which include significant figures and one uncertain figure, and exact numbers, which are clearly defined and obtained from counting or fixed calculations.
  • 📝 When multiplying or dividing significant numbers with exact numbers, the result should contain a number of significant figures corresponding to the significant number with the least amount of significant figures.

Q & A

  • What is scientific notation and why is it used?

    -Scientific notation is a way of writing numbers in the form of a base number multiplied by a power of 10, also known as exponential notation. It is used to simplify the writing of very large or very small numbers, making it easier to perform calculations and understand the scale of measurements.

  • How do you convert a number into scientific notation?

    -To convert a number into scientific notation, you move the decimal point to the right of the first non-zero digit, creating a base number between 1 and 10. Then, you multiply this base number by 10 raised to the power of the number of places you moved the decimal point, which is the exponent.

  • What is the significance of the base number 'a' in scientific notation?

    -In scientific notation, 'a' is the base number or the significant figure part of the number. It must be a real number greater than or equal to 1 and less than 10, ensuring that the notation is standardized and easily comparable.

  • How is the exponent 'n' determined in scientific notation?

    -The exponent 'n' in scientific notation is determined by the number of places the decimal point is moved to achieve the base number 'a'. If the original number is less than 1, 'n' will be negative, indicating the decimal point was moved to the right. If the original number is greater than 1, 'n' will be positive, indicating the decimal point was moved to the left.

  • What are the benefits of using scientific notation in scientific measurements?

    -Scientific notation offers several benefits: it simplifies the writing of significant numbers from measurements, facilitates algebraic calculations, and makes it easier to determine the order of magnitude of the measured quantities.

  • What is the difference between significant figures and estimated figures in measurements?

    -Significant figures include both certain figures, which are directly read from the measuring instrument, and estimated figures, which are uncertain and not directly visible on the scale of the measuring instrument. The last digit in a measurement is usually the estimated figure, while the others are considered certain.

  • How do you determine the number of significant figures in a given number?

    -To determine the number of significant figures, you count all the non-zero digits, any zeros between significant figures, and any trailing zeros in a decimal portion. Leading zeros are not counted as they do not contribute to the precision of the measurement.

  • What is the rounding rule for significant figures when performing arithmetic operations?

    -When rounding numbers to a certain number of significant figures, if the first digit to be discarded is 5 or greater, the last retained digit is increased by one. If it is less than 5, the last retained digit remains the same and the subsequent digits are dropped.

  • How does the number of significant figures affect calculations like addition and subtraction?

    -In addition and subtraction, the result should only contain one estimated figure. If there are multiple estimated figures, the result is rounded to have only one estimated figure, ensuring the precision of the calculation is consistent with the least precise number involved.

  • What is the impact of significant figures in multiplication and division calculations?

    -In multiplication and division, the result should contain the same number of significant figures as the number with the least significant figures in the operation. This ensures the accuracy of the result is not overstated based on the precision of the numbers involved.

  • How should you handle significant figures when dealing with exact numbers in calculations?

    -Exact numbers, such as those derived from counting or defined constants, are treated differently from significant figures obtained from measurements. When combining exact numbers with significant figures, the result should contain a number of significant figures equal to the least number of significant figures in the significant figures involved.

Outlines

00:00

📚 Scientific Notation and Importance of Numbers

The script introduces scientific notation as a method to express very large or small numbers in the form of a base number multiplied by a power of 10. It explains how to convert numbers like the mass of an electron or the size of Jupiter into this notation, emphasizing the ease of writing, calculation, and the determination of the order of magnitude. The video aims to teach the audience about scientific notation and significant figures, highlighting the importance of accurately representing numbers in scientific contexts.

05:01

🔍 Understanding Significant Figures in Measurement

This paragraph delves into the concept of significant figures, which are crucial in scientific measurements. It distinguishes between certain and uncertain digits within these figures, explaining how the last digit is an estimate and the others are certain. The script provides examples of how to determine the number of significant figures in various measurements and the rules for rounding numbers, ensuring that the audience grasps the fundamentals of precision in scientific data representation.

10:04

🔢 Rules for Rounding and Calculating with Significant Figures

The script outlines the rules for rounding numbers to the nearest significant figure and the implications for calculations involving addition, subtraction, multiplication, division, exponentiation, and root extraction. It emphasizes that calculations should only contain a single estimated digit and that the number of significant figures in the result should match the smallest number of significant figures among the operands. This section ensures that viewers understand how to maintain accuracy through proper rounding and calculation techniques.

15:05

📘 Differentiating Between Approximate and Exact Numbers

This section clarifies the difference between approximate and exact numbers. Approximate numbers contain significant figures and an estimate, derived from measurements, while exact numbers are definite and result from counting or established calculations. The script provides examples of exact numbers, such as the number of animals or people, and mathematical constants, and explains the rules for converting between approximate and exact numbers, ensuring that the audience can correctly identify and use different types of numerical data.

20:09

📝 Applying Scientific Notation and Significant Figures in Problems

The final paragraph presents a series of problems that apply the concepts of scientific notation and significant figures. It guides the audience through the process of converting numbers into scientific notation, determining the number of significant figures in given numbers, performing calculations while adhering to the rules of significant figures, and understanding the volume of a cube based on measurement. This practical application reinforces the importance of these concepts in solving scientific problems accurately.

Mindmap

Keywords

💡Scientific Notation

Scientific notation is a method of expressing very large or very small numbers in the form of a base number multiplied by a power of 10. In the video, it is used to simplify the representation of numbers such as the mass of an electron or the size of Jupiter, making them easier to comprehend and work with in scientific contexts. For instance, the mass of an electron is expressed as 9.1 multiplied by 10 to the power of negative 31 kilograms.

💡Exponent

An exponent in mathematics is a way of indicating the number of times a base number is multiplied by itself. In scientific notation, the exponent indicates the power to which the number 10 is raised. The video explains that when converting a number to scientific notation, one must determine the appropriate exponent, such as negative 31 for the electron's mass, to ensure the number is between 1 and 10.

💡Significant Figures

Significant figures are the digits in a number that carry meaningful information about its precision. The video emphasizes the importance of understanding and correctly identifying significant figures in measurements, as they represent the reliability of the data. For example, the video describes how to determine the number of significant figures in a measurement like 4.2 cm, where 4 and 2 are the significant figures.

💡Measurement

Measurement is the process of determining the size, amount, or degree of something. In the context of the video, it relates to obtaining data through tools like rulers or micrometers, which often result in decimal numbers that are considered significant figures. The video script mentions measurement as a common activity in physics where the results are expressed with significant figures.

💡Estimation

Estimation in the video refers to the uncertain part of a measurement that cannot be precisely read on the measuring instrument's scale. It is part of the significant figures and represents the degree of accuracy of the measuring tool. The script explains that the last digit in a measurement is often an estimated value, such as the 0.05 cm in a length measurement of 4.25 cm.

💡Precision

Precision is the degree of exactness or refinement of a measurement. The video discusses how the precision of a measuring instrument is reflected in the number of significant figures, especially the estimated figures. Precision is crucial in scientific work to ensure reliable and reproducible results.

💡Rounding

Rounding is the process of adjusting a number to a certain number of significant figures. The video provides rules for rounding numbers, such as rounding up if the first digit after the decimal is 5 or more, and rounding down if it is less than 5. For example, the number 63.69 would be rounded to 63.7.

💡Exact Numbers

Exact numbers are those that are clearly defined or determined, such as the result of counting indivisible objects or constants in physics equations. The video contrasts exact numbers with measured numbers, which contain significant figures and estimations. Exact numbers, like the number of people or the value of pi, are not subject to estimation.

💡Volume

Volume in the video refers to the amount of space occupied by a three-dimensional object, such as a cube. The script discusses calculating the volume of a cube using the length of its edge, raised to the power of three. The example given is a cube with an edge length of 4.23 cm, and the calculated volume is rounded to three significant figures.

💡Conversion

Conversion in the context of the video is the process of changing a number into scientific notation or adjusting its significant figures. The script provides examples of converting measurements into scientific notation to simplify their expression and ensure they are presented with the correct number of significant figures, such as converting 0.00001350 to 1.4 x 10^-4.

💡Multiplication and Division

Multiplication and division in the video are arithmetic operations that affect the number of significant figures in a result. The video explains that the result of these operations should be rounded to the number of significant figures equal to the smallest number of significant figures of the numbers involved in the operation. For example, multiplying 25.76 (with five significant figures) by 0.015 (with two significant figures) results in a number that should be rounded to two significant figures.

Highlights

Introduction to scientific notation and its importance in simplifying the representation of very large or very small numbers.

Explanation of scientific notation as a method to express numbers in the form of a base times a power of 10.

The rule for writing scientific notation, where 'a' is the base and 'n' is the exponent, with conditions for the values of 'a' and 'n'.

How to convert very small numbers, such as the mass of an electron, into scientific notation by shifting the decimal point.

The process of converting very large numbers, like the mass of Jupiter, into scientific notation by adding a decimal point and shifting it to the left.

Benefits of scientific notation, including ease of writing significant measurement results, simplification of algebraic calculations, and determination of the order of magnitude.

Understanding significant figures in measurements and the distinction between certain and uncertain digits.

The concept of significant figures consisting of both certain and estimated numbers derived from measurement instruments.

How to determine the number of significant figures in a given measurement, with examples and rules.

Rounding rules for significant figures, rounding up if the first uncertain digit is 5 or more, and down if less than 5.

Application of significant figures in arithmetic operations, such as addition and subtraction, where results contain only one estimated digit.

Multiplication and division operations involving significant figures, where the result's significant figures match the smallest count among the numbers involved.

The handling of significant figures in exponentiation and root extraction, maintaining the same count of significant figures as the original number.

Differentiation between approximate numbers, which contain significant figures and one estimated digit, and exact numbers, which are clearly defined and derived from counting or defined relationships.

Practical application of significant figures in solving problems, such as converting a number into scientific notation with a specified number of significant figures.

Examples of calculating the volume of a cube using the significant figures of the length of its edge, demonstrating the rounding process.

Final summary of the importance of understanding scientific notation and significant figures in scientific measurements and calculations.

Transcripts

play00:02

[Musik]

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Halo teman-teman selamat datang kembali

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di channel YouTube Gia Academy Semoga

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teman-teman selalu sehat dan terus

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semangat

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teman-teman dalam ilmu sains kita sering

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menjumpai benda dengan ukuran yang

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sangat kecil atau benda yang sangat

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besar misalnya masa elektron yang bisa

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kita lihat dengan mikroskop elektron

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kira-kira sekecil ini dan masa planet

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Jupiter kira-kira sebesar ini bagaimana

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ya cara membaca masa elektron dan massa

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planet Jupiter tersebut cukup sulit

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bukan ternyata untuk memudahkan kita

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dalam membacanya kita dapat menggunakan

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notasi ilmiah Apa itu notasi ilmiah

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Bagaimanakah cara penulisannya Nah agar

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pertanyaan tadi terjawab kita akan

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membahas materi ini secara lengkap di

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video kali ini

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jadi di video ini kita akan belajar

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tentang notasi ilmiah dan angka penting

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simak terus videonya ya

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nah teman-teman notasi ilmiah adalah

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cara penulisan bilangan secara ilmiah

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dalam bentuk bilangan 10 berpangkat

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notasi ilmiah disebut juga bentuk baku

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atau notasi eksponensial

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cara penulisan notasi ilmiah adalah a

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dikali 10 pangkat n dengan a adalah

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bilangan pokok atau basis berupa

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bilangan real atau angka penting dengan

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nilai a lebih dari atau sama dengan 1

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dan kurang dari 10 n adalah pangkat atau

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eksponen berupa bilangan bulat dan 10

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pangkat n adalah orde

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cara mengubah bilangan yang sangat kecil

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seperti massa elektron dapat kita

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lakukan dengan menggeser tanda koma

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desimal ke sebelah kanan sampai

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diperoleh bilangan pokok atau basis yang

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nilainya lebih dari atau sama dengan

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satu dan kurang dari 10 maka kita dapat

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menggeser sebanyak 31 kali sehingga A =

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9,1 karena kita menggeser ke sebelah

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kanan maka pangkatnya bernilai negatif

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sebanyak kita menggeser koma desimal

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yaitu negatif 31 sehingga diperoleh orde

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10 pangkat negatif 31 jadi bahasa

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elektron adalah

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9,1 kali 10 pangkat negatif 31 kg

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sedangkan cara mengubah bilangan yang

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sangat besar seperti massa planet

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Jupiter dapat kita lakukan dengan

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menambahkan tanda koma desimal di

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belakang angka nol yang terakhir

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kemudian menggesernya ke sebelah kiri

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sampai diperoleh bilangan pokok atau

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basis yang nilainya lebih dari atau sama

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dengan 1 dan kurang dari 10 maka kita

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dapat menggeser sebanyak 27 kali

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sehingga A =

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1,898 karena kita menggeser ke sebelah

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kiri pangkatnya bernilai positif

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sebanyak kita menggeser koma desimal

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yaitu 27 sehingga diperoleh orde 10

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pangkat 27 jadi massa planet Jupiter

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adalah

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1,898 kali 10 pangkat 27 kg

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notasi ilmiah mempunyai beberapa manfaat

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yaitu yang pertama mempermudah dalam

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penulisan angka penting hasil pengukuran

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kedua mempermudah dalam hitungan aljabar

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dan yang ketiga mempermudah dalam

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menentukan orde besaran yang diukur

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sampai di sini teman-teman bisa paham ya

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teman-teman di video sebelumnya kita

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sudah membahas mengenai pengukuran dalam

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kegiatan pengukuran misalnya saat

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mengukur panjang suatu benda dengan

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menggunakan mistar atau penggaris kita

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akan menemukan hasil yang tidak selalu

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bilangan bulat melainkan bilangan

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desimal seperti

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5,2 cm begitu juga saat mengukur

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menggunakan jangka sorong dan mikrometer

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sekrup kita akan memperoleh bilangan

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desimal seperti

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5,24 cm dan

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9,48 cm di dalam fisika

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bilangan-bilangan tersebut merupakan

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angka penting jadi Selanjutnya kita akan

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membahas mengenai angka penting

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angka penting adalah semua Angka yang

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diperoleh dari hasil pengukuran angka

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penting terdiri dari angka pasti dan

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angka taksiran angka pasti adalah angka

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yang Tidak diragukan nilainya dapat

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dilihat atau dibaca pada alat ukur

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sedangkan angka taksiran adalah angka

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yang masih diragukan nilainya tidak

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dapat dilihat atau dibaca pada skala

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alat ukur

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angka taksiran ini merupakan angka

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ketelitian alat ukur yang digunakan

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diperoleh dari setengah dikali skala

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terkecil alat ukur tersebut satu angka

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terakhir dari hasil pengukuran merupakan

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angka taksiran angka lainnya adalah

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angka pasti

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teman-teman bisa memperhatikan Contoh

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angka penting hasil pengukuran besaran

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panjang berikut ini pada gambar tersebut

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angka 4,2 cm adalah angka pasti yang

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terbaca oleh skala alat ukur sedangkan

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0,05 cm adalah angka taksiran yang tidak

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terbaca oleh skala alat ukur hasil

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pengukuran yang terdiri dari angka pasti

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ditambah angka taksiran sebesar

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4,25 cm adalah angka penting kita juga

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bisa menentukan jumlah angka pentingnya

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nah pada contoh ini jumlah angka

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pentingnya adalah 3 ya teman-teman

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untuk menentukan jumlah angka penting

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kita gunakan aturan-aturan berikut

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pertama semua angka Bukan nol adalah

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angka penting contohnya

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156,7 mengandung 4 angka penting

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21,5 mengandung 3 angka penting kedua

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semua angka nol yang terletak diantara

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angka bukan 0 adalah angka penting

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contohnya

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20,35 mengandung 4 angka penting

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367.02 mengandung 5 angka penting ketiga

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angka 0 di sebelah kanan tanda desimal

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dan di sebelah kiri angka bukan 0 bukan

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angka penting contoh

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0,0067 mengandung 2 angka penting 0,

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03 01 mengandung 3 angka penting

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selanjutnya semua angka di sebelah kanan

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tanda desimal dan mengikuti angka bukan

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0 adalah angka penting contohnya

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25,00 mengandung 4 angka penting

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0,007800 mengandung 4 angka penting

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terakhir angka 0 di sebelah kanan angka

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bukan 0 tanpa tanda desimal bukan angka

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penting kecuali diberi tanda khusus

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berupa garis bawah atau garis atas

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contohnya

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13000 tanpa ada yang diberi tanda khusus

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mengandung 2 angka penting

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13000 dengan 10 digaris bawah mengandung

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3 angka penting

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13000 dengan 20 digaris bawah mengandung

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4 angka penting

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berikutnya kita bahas aturan pembulatan

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angka penting pertama angka yang lebih

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besar dari 5 dibulatkan ke atas

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contohnya

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63,69 dibulatkan menjadi

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63,7

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47,48 dibulatkan menjadi

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47,5

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15,77 dibulatkan menjadi

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15,8 sedangkan angka yang lebih kecil

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dari 5 dibulatkan ke bawah misalnya

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23,64 dibulatkan menjadi

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23,6

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47,43 dibulatkan menjadi

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47,4

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15,72 di akan menjadi

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15,7 jika tepat angka 5 lihat bilangan

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sebelumnya jika ganjil maka dibulatkan

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ke atas dan jika genap maka dibulatkan

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ke bawah contohnya

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23,75 dibulatkan menjadi

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23,8 dan

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23,25 dibulatkan menjadi 23,2

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nah teman-teman dalam operasi hitung

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juga ada aturan angka penting pertama

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pada operasi penjumlahan dan pengurangan

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hasil perhitungan hanya boleh mengandung

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satu angka taksiran contohnya pada

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penjumlahan

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564,321 dengan satu sebagai angka

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taksiran ditambah

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25,76 dengan 6 sebagai angka taksiran

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hasilnya

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590,0818 dan 1 adalah angka taksiran

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karena hanya boleh ada satu angka

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taksiran maka hasil perhitungannya

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dibulatkan menjadi

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590,08 selanjutnya pada pengurangan

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715,9 dengan 9 sebagai angka taksiran

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dikurang

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65,74 dengan 4 sebagai angka taksiran

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hasilnya

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650,16 1 dan 6 adalah angka taksiran

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karena hanya boleh ada satu angka

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taksiran maka hasil perhitungannya

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dibulatkan menjadi 650,2

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kedua pada operasi perkalian dan

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pembagian hasil perhitungan mengandung

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jumlah angka penting sesuai dengan

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jumlah angka penting terkecil dari

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bilangan yang dikalikan atau dibagi

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contohnya pada perkalian

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25,761 dengan 5 angka penting dikali

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0,015 dengan 2 angka penting hasilnya

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3,86415 dengan 6 angka penting karena

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jumlah angka penting terkecil adalah 2

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maka hasil perhitungannya dibulatkan

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menjadi

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3,9 selanjutnya pada pembagian

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60,325 dengan 5 angka penting dibagi 400

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dengan satu angka penting hasilnya

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0,15

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08125 dengan 7 angka penting karena

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jumlah angka penting terkecil adalah 1

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maka hasil perhitungannya dibulatkan

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menjadi 0,2

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selanjutnya pada operasi pangkat dan

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penarikan akar hasil perhitungan

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mengandung jumlah angka penting sama

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dengan jumlah angka penting dari

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bilangan yang dipangkatkan atau di akar

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kan contohnya pada perpangkatan

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2,7 yang mengandung dua angka penting

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dipangkatkan 3 hasilnya

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19,683 mengandung 5 angka penting karena

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jumlah angka penting dari bilangan yang

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dipangkatkan adalah 2 maka hasil

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perhitungannya dibulatkan menjadi 20

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dengan 0 diberi garis bawah sedangkan

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pada penarikan akar

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6,25 yang mengandung 3 angka penting

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jika di akar Kan hasilnya 2,5 dengan 2

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angka penting karena jumlah angka

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penting dari bilangan yang diakarkan

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adalah 3 maka hasil perhitungannya

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ditambah angka 0 menjadi

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2,5 nol dengan tiga angka penting

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terakhir pada operasi perkalian antara

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bilangan penting dan bilangan eksak nah

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teman-teman dalam mempelajari angka

play14:56

penting ada dua jenis bilangan yang

play14:58

perlu kita ketahui yaitu bilangan

play15:01

penting dan bilangan eksak bilangan

play15:04

penting adalah bilangan yang mengandung

play15:08

angka-angka penting dan satu angka

play15:11

taksiran serta diperoleh dari suatu

play15:14

pengukuran contohnya panjang meja

play15:18

1,52 meter

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1,52 adalah bilangan penting sedangkan

play15:25

bilangan eksak adalah bilangan yang

play15:28

sudah jelas atau pasti dan diperoleh

play15:31

dari hasil membilang

play15:35

Yang termasuk bilangan eksak diantaranya

play15:38

adalah bilangan hasil penghitungan

play15:41

benda-benda yang tidak dapat dibagi

play15:44

contohnya 6 sapi 4 orang 6 dan 4

play15:49

merupakan bilangan eksak bilangan pada

play15:53

definisi eksak atau pasti contohnya 1

play15:57

jam sama dengan

play15:59

3600 sekon 1 dan 3600 merupakan bilangan

play16:04

ekstrak dan bilangan pada suatu

play16:08

persamaan atau hubungan antar besaran

play16:11

fisis contohnya pada persamaan kecepatan

play16:15

sudut Omega =

play16:18

2p/t sama juga dengan 2 PF atau pada

play16:23

volume bola V =

play16:26

4/3 PR pangkat 3 angka 2 3 dan 4 pada

play16:32

persamaan tersebut merupakan bilangan

play16:35

ekstrak

play16:37

jika kita mengalihkan antara bilangan

play16:40

penting dengan bilangan eksak Maka

play16:43

menurut aturan angka penting hasil

play16:46

perhitungan mengandung jumlah angka

play16:49

penting sesuai dengan jumlah angka

play16:52

penting dari bilangan penting contohnya

play16:56

13,5 yang mengandung 3 angka penting

play17:00

dikalikan dengan 25 yang merupakan angka

play17:05

eksak hasilnya

play17:09

337,5 mengandung 4 angka penting karena

play17:13

jumlah angka penting dari bilangan

play17:15

penting adalah 3 maka hasil

play17:19

perhitungannya dibulatkan menjadi

play17:22

338 sampai di sini teman-teman paham ya

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agar teman-teman semakin paham Mari kita

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selesaikan contoh soal berikut

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soal pertama pada soal ini kita diminta

play17:39

mengubah bilangan

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0,00001350 ke dalam dua angka penting

play17:48

dan sesuai dengan notasi ilmiah terlebih

play17:51

dahulu kita ubah ke dalam bentuk notasi

play17:54

ilmiah ingat kembali aturan penulisan

play17:57

notasi ilmiah Kita tentukan bilangan

play18:00

pokok dengan menggeser koma desimal ke

play18:04

sebelah kanan sampai bilangan pokoknya

play18:07

lebih dari atau sama dengan satu dan

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kurang dari 10 kita peroleh bilangan

play18:13

pokok

play18:15

1,350 yang terdiri dari 4 angka penting

play18:19

kita lakukan pembulatan sehingga

play18:22

bilangan pokoknya menjadi

play18:25

1,4 yang mengandung dua angka penting

play18:28

selanjutnya kita tentukan pangkat karena

play18:32

kita menggeser koma desimal sebanyak 4

play18:35

kali ke kanan maka pangkatnya negatif 4

play18:39

sehingga ordenya 10 pangkat negatif 4

play18:43

jadi hasilnya adalah

play18:46

1,4 dikali 10 pangkat negatif 4

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jawabannya B

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soal kedua kita diminta menentukan

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jumlah angka penting pada bilangan yang

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diberikan bilangan pertama

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0,00670 sesuai dengan aturan angka

play19:08

penting yang ketiga dan keempat maka

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jumlah angka pentingnya adalah 3

play19:14

sedangkan bilangan kedua

play19:18

50,008 sesuai dengan aturan angka

play19:22

penting yang kedua maka jumlah angka

play19:24

pentingnya adalah 5 jadi jawaban yang

play19:27

benar adalah d

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soal selanjutnya kita diminta

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menjumlahkan bahasa buah jeruk apel dan

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jambu sesuai dengan aturan operasi

play19:40

hitung angka penting masa jeruk sama

play19:43

dengan

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3,625 dengan 5 sebagai angka taksiran

play19:50

massa apel

play19:52

3,25 dengan 5 sebagai angka taksiran dan

play19:57

masa jambu sama dengan

play19:59

3,6 dengan 6 sebagai angka taksiran

play20:04

ketiganya dijumlahkan hasilnya

play20:08

10,475 dengan 47 dan 5 sebagai angka

play20:14

taksiran sesuai dengan aturan

play20:16

penjumlahan hasil perhitungan hanya

play20:19

boleh mengandung satu angka taksiran

play20:22

maka kita harus melakukan pembulatan

play20:24

sehingga diperoleh hasil perhitungan

play20:28

10,5 dengan 5 sebagai angka taksiran

play20:32

jadi jawabannya e

play20:36

soal keempat hasil pengukuran panjang

play20:39

dan lebar suatu lantai adalah

play20:43

12,6 meter dan

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5,2 meter kita diminta menentukan luas

play20:50

lantai sesuai dengan aturan angka

play20:53

penting panjang lantai

play20:55

12,6 mengandung 3 angka penting

play20:59

sedangkan lebar lantai 5,2 mengandung 2

play21:04

angka penting hasil perkalian keduanya

play21:06

adalah

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65,52 mengandung 4 angka penting ingat

play21:13

kembali bahwa hasil perhitungan pada

play21:16

operasi perkalian sama dengan jumlah

play21:19

angka penting terkecil dari bilangan

play21:22

yang dikalikan karena jumlah angka

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penting terkecil adalah 2 maka hasil

play21:28

perhitungannya dibulatkan menjadi

play21:31

66 jadi luas lantai adalah 66

play21:36

meter kuadrat jawabannya e

play21:41

soal terakhir Raisa melakukan eksperimen

play21:44

pengukuran volume kubus menggunakan

play21:47

jangka sorong hasil pengukuran panjang

play21:50

rusuk sebesar

play21:52

4,23 cm kita diminta menentukan volume

play21:57

kubus tersebut berdasarkan aturan angka

play22:00

penting panjang rusuk kubus sama dengan

play22:04

4,23 cm mengandung 3 angka penting untuk

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menghitung volume panjang rusuk kita

play22:12

pangkatkan tiga hasilnya

play22:20

75,686967 cm ^ 3 mengandung 8 angka

play22:25

penting ingat kembali aturan

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perpangkatan angka penting hasil

play22:31

perhitungan mengandung jumlah angka

play22:33

penting sama dengan jumlah angka penting

play22:36

bilangan yang dipangkatkan karena jumlah

play22:39

angka penting dari bilangan yang

play22:42

dipangkatkan adalah 3 maka hasil

play22:45

perhitungannya dibulatkan menjadi

play22:49

75,7 cm pangkat 3 jadi jawaban yang

play22:53

benar adalah e

play22:57

Oke teman-teman demikianlah pembahasan

play23:00

kita tentang notasi ilmiah dan angka

play23:03

penting jangan lupa tonton terus

play23:06

video-video terbaru di channel kita ya

play23:08

sampai jumpa di video berikutnya

play23:12

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