Lesson 7.2

EM waves travel at what speed in a vacuum?

• 300,000 m/s

• 300,000,000 km/s

Answer explanation

This question links to success criteria: I can explain what an electromagnetic wave is and how it travels through different materials.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Which of the following best describes what an electromagnetic wave is?

• The last mystery science cannot solve.

• An electrical charge spinning very fast as it moves forward.

• two transverse waves at right angles to each other, one being a magnetic field and one being an electric field.

• Two longitudinal waves on top of each other made out of tiny magnets.

Answer explanation

This question links to success criteria: I can explain what an electromagnetic wave is and how it travels through different materials.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Select the correct order of waves on the EMS from low energy on the left to high energy on the right.

• X-ray

• Infrared, Visible, and ultraviolet

• Microwave

• Radio wave

• Gamma

Answer explanation

This question links to success criteria: I can identify how wavelength, frequency and energy change along the electromagnetic spectrum.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Which of the following are important differences between mechanical and electromagnetic waves?

• Electromagnetic waves can travel without a medium

• Electromagnetic waves do not have wavelengths

• Electromagnetic waves move faster in a less dense medium than in a more dense medium

• Electromagnetic waves do not change speed when changing medium

Answer explanation

This question links to success criteria: I can explain what an electromagnetic wave is and how it travels through different materials.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Select the correct order of waves on the EMS from low frequency on the left to high frequency on the right.

• Radio wave

• X-ray

• Infrared, Visible, and ultraviolet

• Microwave

• Gamma

Answer explanation

This question links to success criteria: I can identify how wavelength, frequency and energy change along the electromagnetic spectrum.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Select the correct order of waves on the EMS from short wavelength on the left to long wavelength on the right.

• Infrared, Visible, and ultraviolet

• Radio wave

• Gamma

• X-ray

• Microwave

Answer explanation

This question links to success criteria: I can identify how wavelength, frequency and energy change along the electromagnetic spectrum.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

When examining an electromagnetic wave in a vacuum, any time the wavelength gets shorter, which of the following must be true?

• The frequency gets higher

• The wave gets faster

• The wave gets slower

• The frequency gets lower

Answer explanation

This question links to success criteria: I can describe the relationship between speed of light, wavelength and frequency and use this relationship to determine missing values.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

A radio wave is detected moving through space with a frequency of 101,500,000 Hz. What is the wavelength of this radio wave?

Reminder, light in a vacuum travels at 300,000,000 m/s

• 2.96m

• 0.34m

• 1985m

• 0.00005891m

Answer explanation

This question links to success criteria: I can describe the relationship between speed of light, wavelength and frequency and use this relationship to determine missing values.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

Televisions are named after the television waves that were used to transmit early television signals. These are a form of light. If one is traveling through space with a wavelength of 10m, what is its frequency?

Answer explanation

This question links to success criteria: I can describe the relationship between speed of light, wavelength and frequency and use this relationship to determine missing values.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.

When examining an electromagnetic wave in a vacuum, any time the frequency gets lower, which of the following must be true?

• The wavelength gets longer

• The wave gets faster

• The wave gets slower

• The wavelength gets shorter

Answer explanation

This question links to success criteria: I can describe the relationship between speed of light, wavelength and frequency and use this relationship to determine missing values.

If you got it correct place a check mark in the question results section. If you got it incorrect place an X in that section. If this was a redemption question, cross out the one X and replace it with a check mark.