Waves Post-Test Review

What is a major difference between electromagnetic waves and mechanical waves?

• Electromagnetic waves require a medium and mechanical waves do not require a medium

• Mechanical waves require a medium and electromagnetic waves do not require a medium

• Electromagnetic waves are unable to travel through a medium

• Mechanical waves are unable to travel through a medium

Which of the following has the shortest wavelength?

• Gamma ray

• Red light

• Radio waves

• Microwaves

An electromagnetic wave with a long wavelength also has which of the following?

• High frequency and high energy

• Low frequency and low energy

• High frequency and low energy

• Low frequency and high energy

Diamonds have a refractive index of 2.42. What happens to a ray of light as it travels from the air through a diamond?

• It multiplies the brightness as it goes through the diamond

• It reflects back to the source

• It cancels out completely

• It changes direction as it goes through the diamond

What is the relationship between speed of light and the index of refraction based on the data below?

• As refractive index goes up, speed goes down

• As refractive index goes up, speed goes up

• As refractive index goes up, speed stays the same

• None of the options are correct

A woman is standing on the sidewalk next to a quiet road. Then, an ambulance begins to approach her with its siren on. It passed by her and then continued down the road ahead. At what point does the siren have the highest pitch to the woman?

• When it starts to approach her

• When it is right next to her

• When it has passed her

• None of the above

Which best describes the Doppler effect?

• When an object moves, there is no distortion of the waves produced by that object

• When an object moves, there is distortion of the waves produced by that object, changing the frequency

• When an object moves, the type of wave changes

• When an object moves, the waves produced by it are destroyed.

You sit by a pond on a cloudless, windless day. The pool of water is perfectly still and when you look into it, you see an image of yourself looking back at you. Which of the following is happening to light waves to let you see an image of yourself?

• Reflection

• Refraction

• Diffraction

• Interference

Two waves interact. They have the same frequency and are perfectly in-line with each other, so we say they are “in phase.” What happens to the amplitude as a result of two “in phase” interactions?

• They form a wave with a smaller amplitude than the individual waves had

• They form a wave with a larger amplitude than the individual waves had

• The waves cancel each other out entirely

• The waves produce two new waves with shorter wavelengths

Which answer contains the parts of the wave that are labelled in Figure 1?

• Compression, rarefaction, equilibrium (resting point)

• Trough, crest, wavelength

• Equilibrium (resting point), crest, compression

• Crest, amplitude, equilibrium (resting point)