Grade 10 SCIENCE | Quarter 2 Module 2 PART 1 | EM Wave Calculations (Wavelength and Frequency)

Summary

This video focuses on solving problems related to electromagnetic waves, specifically involving wavelength, frequency, and energy. It begins with a quick recap of electromagnetic wave properties, types, and contributions from scientists in the field. The host explains key concepts like frequency, energy, and wavelength, along with important constants such as the speed of light and Planck's constant. Several formulas and examples are presented to calculate wavelength and frequency, with step-by-step problem-solving techniques to guide viewers in applying these formulas effectively.

Takeaways

• 📚 Quick recap on electromagnetic waves: Definition, properties, and the 7 types (radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, gamma rays).
• 📊 Electromagnetic waves are arranged in the electromagnetic spectrum where wavelength decreases and frequency increases from radio waves to gamma rays.
• 👨‍🔬 Discussion of scientists who made significant contributions to the study of electromagnetism and electromagnetic theory.
• ⚡ Focus of the module: Solving problems related to the wavelength, frequency, and energy of electromagnetic waves.
• 📏 Formula for electromagnetic waves: c = λf, where c is the speed of light, λ is the wavelength, and f is the frequency.
• 📐 Speed of light in a vacuum (c) is a constant at 3 x 10^8 meters per second, which is used in calculations involving wave properties.
• 🔬 Planck’s constant (h) is 6.63 x 10^-34 joules per second, important for solving energy-related problems.
• 🧮 Step-by-step process for solving wavelength and frequency problems, including sample problems involving radio waves and light.
• 🎯 Key formulas for calculating frequency (f = c/λ) and wavelength (λ = c/f) depending on what values are given.
• 📡 Example problems include calculating the frequency and wavelength of radio waves, and understanding units like meters and hertz.

Q & A

What are the seven types of electromagnetic waves mentioned in the video?

The seven types of electromagnetic waves are radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma rays.

How are electromagnetic waves arranged in the electromagnetic spectrum?

Electromagnetic waves are arranged in the electromagnetic spectrum from radio waves to gamma rays, with wavelength decreasing and frequency increasing as you move through the spectrum.

What is the formula that relates wavelength and frequency in an electromagnetic wave?

The formula is c = λf, where c is the speed of light (3 x 10^8 meters per second), λ is the wavelength in meters, and f is the frequency in hertz.

What is Planck’s constant and its value?

Planck's constant (h) is 6.63 x 10^-34 joules second, and it is used in calculations involving the energy of electromagnetic waves.

What is the frequency of an electromagnetic wave with a wavelength of 150 meters?

The frequency is 2 x 10^6 hertz. This is calculated using the formula f = c / λ, where c is 3 x 10^8 m/s and λ is 150 meters.

How would you calculate the wavelength of an electromagnetic wave if the frequency is given?

You can calculate the wavelength using the formula λ = c / f, where c is the speed of light and f is the frequency.

What is the frequency of a radio wave with a wavelength of 0.52 meters?

The frequency of a radio wave with a wavelength of 0.52 meters is 5.77 x 10^8 hertz.

What is the wavelength of an electromagnetic wave with a frequency of 8 x 10^14 hertz?

The wavelength is 3.75 x 10^-7 meters, calculated using the formula λ = c / f.

What is the wavelength of an FM radio signal that broadcasts at 107.9 hertz?

The wavelength of an FM radio signal broadcasting at 107.9 hertz is 2.78 x 10^6 meters.

Why is it important to remember the exponent when calculating with scientific constants?

It is important to remember the exponent because it significantly affects the magnitude of the value, especially when dealing with very large or very small numbers in scientific calculations.