Pembahasan Soal Alat Ukur dan Daya Listrik sederhana
Summary
TLDRThe transcript discusses various electrical concepts through calculations and diagrams. It explains how to measure current using a scale and calculates resistance using Ohm's law with a voltmeter and ammeter. The script also covers calculating power and energy consumption of a 60W light bulb at different voltages and durations, and determines the required length of a heating wire based on its resistance and voltage. It's a comprehensive tutorial on basic electrical principles and calculations.
Takeaways
- 🔍 The script discusses the calculation of electric current using a scale, where the measured current is 1/3 ampere based on the given scale.
- 🔌 It explains the use of a voltmeter and an ammeter to measure resistance (Rx), with the voltmeter having a resistance of 1 kilo Ohm and the ammeter having a resistance of 1 Ohm.
- ⚡ The calculation of Rx involves using Ohm's law (V = IR), where V is the voltage across the resistor, I is the current through the resistor, and R is the resistance.
- 💡 The script covers the concept of power in electrical circuits, including the calculation of power (P) and energy (E) for a light bulb with a rated power of 60 watts and a voltage of 220 volts.
- 🕒 The energy consumption of the light bulb is calculated over a period of 30 minutes, taking into account the power rating and the time it is used.
- 🔥 The script also discusses the power rating of a heating device and how it relates to the resistance and voltage of the wire used.
- ⏱ The calculation of the required length of wire for the heating device is based on the resistance per meter of the wire and the desired power output.
- 📏 The resistance of the wire is considered constant, and the voltage used is 125 volts, which is used to determine the necessary wire length.
- 📐 The script provides a step-by-step approach to solving electrical problems, including the use of Ohm's law and Kirchhoff's current law.
- 📋 The final calculations involve simplifying and solving equations to find the unknown variables such as the resistance (Rx) and the length of the wire needed for the heating device.
Q & A
What is the measured current if the scale reads 30 on a maximum scale of 90 with a maximum current of 1 ampere?
-The measured current is 1/3 ampere, calculated by dividing the scale reading (30) by the maximum scale (90) and then multiplying by the maximum current (1 ampere).
What is the resistance (Rx) measured by the voltmeter and ammeter when the voltmeter reads 5 volts and the ammeter reads 25 milliamperes?
-The resistance (Rx) is calculated using Ohm's law, V = I * Rx, where V is 5 volts and I is the total current which is 25 milliamperes (0.025 amperes). The calculated resistance is 5 volts / 0.025 amperes, which equals 200 ohms.
How do you calculate the total current flowing through the circuit when the ammeter reads 25 milliamperes and there's a known current分流 through another path?
-To find the total current, you use Kirchhoff's current law which states that the total current entering a junction is equal to the total current leaving the junction. If the分流 current is known, you add it to the ammeter reading (25 milliamperes) to get the total current.
What is the power consumption of a 60-watt light bulb when connected to a 220-volt supply for 30 minutes?
-The power consumption is calculated by multiplying the power rating of the bulb (60 watts) by the time it is on (30 minutes converted to hours, which is 0.5 hours). So, the energy consumed is 60 watts * 0.5 hours = 30 watt-hours.
How do you determine the resistance of a filament in a light bulb if it's rated for 60 watts at 220 volts?
-Using the formula P = V^2 / R, where P is power, V is voltage, and R is resistance. Rearranging to solve for R gives R = V^2 / P. Substituting the given values (V = 220 volts, P = 60 watts) gives R = 220^2 / 60, which equals approximately 807.67 ohms.
What is the required length of wire for a 200-watt heating element with a resistance of 25 ohms per meter when used at a voltage of 125 volts?
-Using the formula R = (V^2 / P) * L, where R is the resistance per meter, V is the voltage, and P is the power. Rearranging to solve for L gives L = (P / (V^2 / R)). Substituting the given values (P = 200 watts, V = 125 volts, R = 25 ohms) gives L = (200 / (125^2 / 25)), which equals approximately 1.6 meters.
How do you calculate the resistance of a wire if the power rating and voltage are known?
-The resistance can be found using the formula R = V^2 / P, where V is the voltage and P is the power rating. This formula is derived from the power formula P = V * I, where I is the current, and Ohm's law V = I * R.
What is the energy consumption in kilojoules of a 15-watt device running for 30 minutes?
-First, convert the power to watt-minutes (15 watts * 30 minutes = 450 watt-minutes). Then, convert watt-minutes to kilojoules (450 watt-minutes / 60 = 7.5 kilojoules, since 1 watt-minute equals 1/60th of a kilojoule).
How do you find the total resistance in a parallel circuit when the individual resistances and the voltage across the circuit are known?
-In a parallel circuit, the total resistance (Rt) can be found using the formula 1/Rt = 1/R1 + 1/R2 + ... + 1/Rn, where R1, R2, ..., Rn are the individual resistances. If the voltage is known, you can also calculate the current through each resistor and then use the above formula.
What is the formula to calculate the power consumption of an electrical device?
-The power consumption (P) of an electrical device is calculated using the formula P = V * I, where V is the voltage and I is the current. Alternatively, if the resistance (R) is known, it can also be calculated using P = V^2 / R or P = I^2 * R.
Outlines
🔌 Electrical Measurement and Ohm's Law Application
This paragraph discusses the process of reading an electric current from a scale diagram and calculating the current using the formula: measured current = (scale reading / maximum scale) * maximum current. It then moves on to explain the measurement of resistance using a voltmeter with a resistance of 1 kilo-ohm and an ammeter with a resistance of 1 ohm. The key concept is applying Ohm's law to find the unknown resistance (Rx) using the formula Rx = Vx / Ix, where Vx is the voltage across the unknown resistance and Ix is the current through it. The paragraph also involves the application of Kirchhoff's current law to ensure the conservation of charge at a junction in a circuit.
💡 Power and Energy Calculations for Lighting and Heating Devices
The second paragraph delves into the calculation of power and energy for a light bulb and a heating device. It starts with a 60-watt light bulb operating at 220 volts and calculates the actual power consumption when the voltage is different from the rated voltage, using the formula P = V^2 / R. The paragraph then calculates the energy consumption of the light bulb over a period of 30 minutes using the formula E = P * t. Subsequently, it discusses the power rating of a heating device and the required length of a wire with a resistance of 25 ohms per meter, given a voltage of 125 volts and a power rating of 200 watts. The final calculation determines the length of the wire needed using the formula for resistance per unit length and the total resistance required.
📏 Calculation of Wire Length for a Heating Element
This paragraph focuses on the calculation of the wire length needed for a heating element with a resistance of 25 ohms per meter. It uses the previously calculated resistance and power values to determine the length of the wire required for the heating element to operate at the desired power. The calculation involves dividing the total resistance needed by the resistance per meter of the wire to find the length. The paragraph also simplifies the fraction obtained from the division to provide a clear and concise answer for the wire length in centimeters.
Mindmap
Keywords
💡Ammeter
💡Voltmeter
💡Resistance (R)
💡Ohm's Law
💡Kirchhoff's Laws
💡Wattage
💡Voltage (V)
💡Current (I)
💡Energy (E)
💡Power (P)
💡Electrical Circuit
Highlights
Calculation of measured current using a scale from an electric current image.
Explanation of maximum scale and current measurement with a 1-ampere maximum current.
Determination of the actual measured current as 1/3 ampere using the given scale and maximum current.
Introduction to measuring resistance using a voltmeter with a 1 kilo-Ohm and an ammeter with a 1-Ohm resistance.
Setup for measuring resistance X using a parallel circuit configuration.
Readings of 5 volts and 25 milliamperes are used to calculate the resistance X.
Application of Ohm's law to find the resistance X using the formula RX = V/I.
Use of Kirchhoff's current law to determine the total current in the circuit.
Calculation of the current through the voltmeter and ammeter to find the total current.
Determination of the resistance X using the total current and voltage across the voltmeter.
Calculation of the resistance X as 50 Ohms using the given voltage and current values.
Analysis of a light bulb with a 60-watt rating and a 220-volt specification.
Adjustment of power calculation for a light bulb when connected to a different voltage.
Calculation of energy consumption for the light bulb when operating for 30 minutes.
Introduction to calculating the required length of a heating element wire with a 200-watt power rating.
Determination of the wire length needed for the heating element based on resistance and voltage.
Final calculation of the wire length as 3.125 meters for the heating element.
Transcripts
Hai yang soal yang sederhana ini ya yang
pertama pembacaan arus listrik dari
gambar dibawah ini kita perhatikan
gambar dibawah ini ini jarum menunjukkan
diangkat 30 ini adalah skala yang
terukur kemudian 90 ini adalah skala
maksimum dan ini eh kabelnya mencolok
pada arus maksimum 1 ampere ya kita bisa
menghitung besarnya arus yang terukur i5
dengan skala yang terbaca ya dibagi
skala maksimum dikali arus maksimum jadi
ini sama dengan skala yang terbacanya
disini 30 kalau maksimumnya disini 90
dikali arus maksimum nya disini 1ampere
jadiin = 1/3 ampere dah Selanjutnya
cce untuk nomor dua ya selanjutnya kita
lihat kesini Perhatikan gambar di bawah
di samping ini di bawah ya voltmeter
memiliki hambatan 1 kilo Ohm ampere M
memiliki hambatan 1 Ohm kedua alat ini
digunakan untuk mengukur hambatan X
menggunakan rangkaian seperti gambar
pada feat terbaca 5volt padaa terbaca 25
mili ampere besarnya hambatan x adalah
di sini diketahui voltmeter memiliki
hambatan 1 kg kita kasih nama disini
berarti disitu ada rr1 kilo Ohm detik di
sini ada hambatan kemudian ampere M
memiliki hambatan berarti disini ini ada
er amperemeter satu Om dan voltmeter
K5 fold batik tegangan ujung-ujung sini
ini 5 volt dan ampere meter terbaca 25
mili ampere disini adalah 25 mili ampere
yang ditanyakan adalah besarnya hambatan
r x ya RX yang ditanyakan adalah rxr itu
= V dibagi Iya menurut ke hukum Om VX
dibagi x VX ya Ini karena rangkaiannya
paralel ya titik-titik ini ini
ujung-ujung voltmeter ujung-ujung
voltmeter sama dengan tegangan VX jadi
VX sudah diketahui fixnya = 5 volt
kemudian disini ada snack ini yang 25
mili ampere ini bukan YKS tapi ini
adalah harus total ya nabati Kita harus
mencari x-men di sini ya ekspedisi ini
berapa harus total kita gunakan hukum2
om Eh hukum 2 Kirchoff i
harus yang masuk itu sama dengan arus
yang keluar ke satu titik misalnya
titiknya di sini titik O berarti arus
yang masuk ke titik O itu adalah arus
maksimum ini ya atau boleh juga arus
yang keluar harus yang keluar kesini
adalah I yang mengalir ke ampere meter
kemudian di sini ada I X dan di sini ada
i v arus yang masuk itu adalah IV dan V
X jadi Ive tambahi X gitu ya sama dengan
arus yang keluarnya adalah yang 25 inii
total ip-nya kita gunakan hukum Om lagi
ya Ih sama dengan Viper er FTV expert
efek eh sorry disitu Vivia seri ini
tegangan untuk voltmeter ngerti ini V
voltmeter dibagi vs lagi deh dibagi er
hot m gitu ya ditambahi FC mau kita cari
= i
leave itu adalah 5volt dibagi Rp nya itu
adalah satu kilo Ohm jadi 1000 m
ditambah qxc kita mau cari = I ini 25
Mili 25/1000 ya 25 milik ah Kita cari
sekarang kita cari dulu Berarti IC nya
itu sama dengan 25/1000 dikurangi 5/1000
= 20 per 1000 Ampere atau 25000000000 20
mili ampere udah sekarang kita masukkan
ke RX RX = V Xperia E X = voltmeter tadi
5 dibagi Yes sajalah 20100mah ke atas
jadi 5000 per 20 =
50 Om selanjutnya nomor tiga pada sebuah
lampu pijar tertulis 60watt 6 What itu
satuan untuk daya daya lampu pijar
kemudian ini tegangannya 220volt V lampu
pijar nya 220volt lampu terpasang pada
tegangan ini tegangan yang dipasang V
selama 30 menit berarti t maka besar
daya lampu dan energi yang timbul daya
itu PN Ergi itu W atau Eya kita cari
dulu kayaknya P pada p yang digunakan
itu tidak sama dengan 60watt Kenapa
karena tegangannya itu dipasang pada
tegangan yang berbeda ya Jadi kita harus
mencari dulu disini apa yang tidak
berubah ketika tegangannya 220 dayanya
60watt apa yang tidak berubah disitu
padahal
Hai itu adalah hambatannya truk kita
lihat P itu = v kuadrat er jadi ini P
lampu er lampu ya gitu nah ketika
220volt dayanya 60watt haba tanyakan
konstan jadi kita bisa cari er lampunya
itu sama dengan file kuadrat per PL atau
sama dengan 220/50 220 kuadrat gitu ya
maka daya yang digunakan up aksen ya ada
yang digunakan pada tegangan 110v itu V
yang 110 cord dibagi RL jadi 110 kuadrat
per er elne itu tadi adalah 220 kuadrat
pernah 60 naik ke atas ya nih sama
dengan satu 11/22 1/2 kuadratnya 1/2
kuadrat kali 60 jadi
empat kali 60 = 15 lewat Nah sekarang
kita tentukan energinya energi itu
adalah PK Lite ya energi x = p * t atau
boleh juga ya kayaknya tadi udah ada
15watt pengennya 30 menit buat dalam
second w30 kali 60 jadi sama dengan
berapa nih 15 kali dua 3030 ikan 15 Aduh
ini rada lolang itunya ya 30 kali dua ya
Jadi ini tiga kali tiga kali tiga
Rp27.000 jual atau sama dengan 27
kilojoule casual terakhir seseorang ini
buat sebuah alat pemanas 200watt 200watt
itu berarti P lagi ya dari suatu kawat
yang mempunyai hambatan 25 Ohm tiap
meter diketahui ini 25 Om tiap meter
berarti ini Rp relnya ya er pr-nya 25 Om
permeter bila hambatan kawat dianggap
konstan dan tegangan yang dipakai 125
volt maka panjangnya kawat yang
diperlukan adalah maksudnya disini
hambatan jenis ya hambatan jenis kawat
nya konstan maka panjangnya kawat yang
diperlukan adalah ini digunakan pada
tegangan V ya Nah kita lihat p sama
dengan v kuadrat per er jadi r-nya = v
kuadrat perfect venue tadi 125 kuadrat
per kayaknya adalah 200 jadi ini sama
dengan 125 kali 125/250 Biarkan saja
dulu jangan
dihitungnya Mas sekarang di sini yang
ditanyakan adalah panjang kawat yang
diperlukan kita tahu kalau er itu sama
dengan ro elber a Jadi kalau hambatan
jenis kawat nya tetap luas penampang
udah pasti sama ya maka alternatifking4d
banding dengan l gitu ya Jadi kalau ada
ini tadi 25 sore ini tadi ada 25 Om per
meter per meternya itu 25 Om sekarang
kita butuh 125 Kalisat 25/200 sudah kita
masukkan aja RL itu sama dengan 25 Om
sama dengan 125 kali 125 R 200 gitu ya
jadi
Hai r-nya airnya kita kalikan ini 25l ya
25 l = 125k Lee 1-25 per 206 kita
sekarang kali silang jadi l-nya sama
dengan kita bagi dengan 25 kiri-kanan ya
kiri kanan kita bagi dengan 25 25
websites 25125 bagi 25 itu adalah lima
200 bagi lima itu adalah 200 dibagi lima
berapa 200 dibagi lima itu adalah 40 Ya
jelas sebagai 5/40 habis ini jadi 125
per 40 kita Sederhanakan dibagi lima itu
25 per delapan
Mbak 25/8 itu adalah ketiga ya 3,8 25
bagi delapan 3,6 tanyakan 1 10 ke-8
3,125
Hai atau berapa 312 koma 5 cm
Weitere ähnliche Videos ansehen
Resistance of a Wire - GCSE Science Required Practical
Ohm’s Law Tutorial with easy practice problems | Basic Circuits
Circuit Analysis: Crash Course Physics #30
FISIKA Kelas 12 - Energi dan Daya Listrik | GIA Academy
Electric Current & Circuits Explained, Ohm's Law, Charge, Power, Physics Problems, Basic Electricity
What are VOLTs, OHMs & AMPs?
5.0 / 5 (0 votes)