HW #5 - Lesson 8.1 Waves Practice Problems Quizizz

A motor is used to produce 4.0 waves each second in a string. What is the frequency of the waves?

• 0.25 Hz

• 15 Hz

• 25 Hz

• 4 Hz

Answer explanation

The frequency of the waves is determined by the number of waves produced per second, which in this case is 4. Therefore, the frequency is 4 Hz.

Tags

NGSS.HS-PS4-1

In a vacuum, light with a frequency of 5.0 x 10^14 hertz has a wavelength of...

• 6.0 x 10^-21 m

• 6.0 x 10^ -7 m

• 1.7 x 10^6 m

• 1.5 x 10^23 m

Answer explanation

Light with a frequency of 5.0 x 10^14 Hz corresponds to a wavelength of 6.0 x 10^-7 m according to the speed of light formula: wavelength = speed of light / frequency.

Tags

NGSS.HS-PS4-1

A change in the speed of a wave as it enters a new medium produces a change in...

• frequency

• period

• wavelength

• phase

Answer explanation

When a wave enters a new medium, its speed changes, causing a change in wavelength while frequency remains constant. Therefore, a change in the speed of a wave entering a new medium produces a change in wavelength.

Tags

NGSS.HS-PS4-1

Compared to the period of a wave of red light the period of a wave of green light is...

• less

• greater

• the same

Answer explanation

The correct answer is 'less' because the period of a wave is inversely proportional to its frequency, and green light has a higher frequency than red light.

Tags

NGSS.HS-PS4-1

A surfacing whale in an aquarium produces water wave crests having an amplitude of 1.2 meters every 0.40 second. If the water wave travels at 4.5 meters per second, the wavelength of the wave is...

• 1.8 m

• 2.4 m

• 3.0 m

• 11 m

Answer explanation

The wavelength of the wave can be calculated using the formula: wavelength = wave speed / frequency. Therefore, wavelength = 4.5 m/s / (1/0.40 s) = 1.8 m. Hence, the correct answer is 1.8 m.

Tags

NGSS.HS-PS4-1

What is the period of a wave if 20 crests pass an observer in 4 seconds?

• 80 s

• 0.2 s

• 5 s

• 4 s

Answer explanation

The period of a wave is the time it takes for one complete cycle. Since 20 crests pass in 4 seconds, the period is 4 seconds / 20 crests = 0.2 seconds per crest.

Tags

NGSS.HS-PS4-1

Which type of wave requires a material medium through which to travel?

• sound

• radio

• television

• x-ray

Answer explanation

Sound waves require a material medium, such as air or water, to travel. Radio, television, and x-ray waves can travel through a vacuum.

Calculate the wavelength in a vacuum of a radio wave having a frequency of 2.2 x 10^6 Hz.

• 3 x 10^8 m

• 2.2 x 10^6 m

• 7.33 x 10^-3 m

• 136 m

Answer explanation

The wavelength of a radio wave can be calculated using the formula: wavelength = speed of light / frequency. Plugging in the values (3 x 10^8 m/s / 2.2 x 10^6 Hz) gives a result of 136 m, which matches the correct answer choice.

Tags

NGSS.HS-PS4-1

A student standing on a dock observes a piece of wood floating on the water. As a water wave passes, the wood moves up and down, rising to the top of a wave crest every 5.0 seconds. The distance between each adjacent crest is 2.0 meters. Calculate the frequency of the passing water waves.

• 2 Hz

• 5.0 Hz

• 10 Hz

• 0.2 Hz

Answer explanation

The frequency of the water waves is calculated by the reciprocal of the time period, which is 1/5.0 = 0.2 Hz. Therefore, the correct answer is 0.2 Hz.

Tags

NGSS.HS-PS4-1

A student standing on a dock observes a piece of wood floating on the water. As a water wave passes, the wood moves up and down, rising to the top of a wave crest every 5.0 seconds. The distance between each adjacent crest is 2.0 meters. Calculate the speed of the water waves.

• 0.4 m/s

• 10 m/s

• 0.1 m/s

• 2.5 m/s

Answer explanation

The speed of the water waves can be calculated using the formula speed = wavelength / period. Given the distance between crests is 2.0 meters and the period is 5.0 seconds, the speed is 2.0 / 5.0 = 0.4 m/s. Therefore, the correct answer is 0.4 m/s.

Tags

NGSS.HS-PS4-1