Chapter 14 Waves

19 T/F, 10 MCQ, 4 SAQ

As the frequency of the wave increases, what happens to the speed and the wavelength?

Speed stays the same, and wavelength decreases.

Does light travel faster through a solid or in a vacuum?

In a vacuum

Can waves transport energy and matter?

They transport energy, but not matter.

Do visible light waves require a medium to travel?

No

Are radio waves electromagnetic waves?

Yes

Are sound waves longitudinal waves?

Yes

Are light waves transverse waves?

Yes, light waves are transverse waves with electric and magnetic fields oscillating perpendicular to their direction of travel.

The energy of mechanical waves depends on the amplitude of the wave. (True/False)

True, the larger the amplitude, the more energy carried through the medium.

As the frequency of the sound wave increases, what happens to the wavelength of the sound waves?

As the frequency of sound increases, its wavelength decreases because speed stays constant.

As the period of a wave increases, does the frequency increase or decrease?

Frequency decreases, as frequency equals one divided by period.

Is the speed of sound at high altitude different from the speed of sound at low altitudes?

Yes, sound travels slower at high altitude due to colder, thinner air that reduces sound speed.

The color of visible light depends on the wavelength of the light. (True/False)

True, as each visible color corresponds to a specific wavelength/freq of light.

When a wave reflects off a fixed boundary, the wave changes direction and what?

When a wave reflects off a fixed boundary, it changes direction and inverts.

What is the doppler effect?

It is the change in observed frequency/pitch of a wave caused by relative motion between source and observer.

When two waves are in the same place at the same time, what kinds of things can happen?

They interfere, causing constructive interference, destructive interference or complex superposition.

What is a node?

It is a loop of a standing wave separated from the next loop by points that have no vibration.

What is destructivie interference?

Destructive interference occurs when waves combine out of phase so their amplitudes partially or completely cancel.

What is diffraction?

Diffraction is the bending and spreading of waves as they pass around obstacles or through narrow openings.

What is a sound wave?

A sound wave is a mechanical longitudinal wave that goes through a medium via compressions and rarefactions.

What is a light wave?

A light wave is an electromagnetic transverse wave formed by oscillating electric and magnetic fields that can travel thru vacuum or matter.

Are light waves electromagneticc waves?

Yes, light waves are electromagnetic waves and are part of the electromagnetic spectrum.

What kind of a medium do seismic waves travel thru?

Seismic waves travel through Earth’s materials, such as rock and soil, and can move through both solid interior and along the surface.

What is a wave front?

A wave front is an imaginary surface connecting points on a wave that all share the same phase, such as all crests.

The frequency of a sound wave determines the _______ of the sound?

The frequency of a sound wave determines the pitch of the sound.

What determines how loud a sound will be?

Loudness mainly depends on the sound wave’s amplitude. (Larger is louder.)

What is the difference between visible light and x-ray?

Both are electromagnetic waves, but x-rays have much higher frequency and energy and much shorter wavelength than visible light.

Which type of electromagnetic wave has the greatest wavelength?

Radio waves have the greatest wavelength.

What is a standing wave?

A standing wave is a pattern of vibration that simulates a waves that is standing still.

Explain the difference between mechanical waves and electromagnetic waves.

Mechanical waves require a medium and involve vibrations, electromagnetic waves do not need a medium and consist of oscillating electric and magnetic fields, able to go through vacuum.

Explain the relationship between mechanical waves and electromagnetic waves?

Both are ways energy travels as waves and share similar properties such as wavelength frequency amplitude and behaviors such as reflection, refraction, interference and diffraction.

Sound waves are mechanical transverse waves. (T/F)

False, as sound waves are mechanical longitudinal waves.

Light waves are electromagnetic waves and can not travel through vacuum. (T/F)

False, as light waves are electromagnetic waves that can travel through vacuum or matter.