Unit 4 - Waves and Electricity Review

Sound waves and ultraviolet light waves both share the property of being able to...

• move through space

• travel at 300,000 m/s

• carry energy

• propagate through rock

A truck is blowing its horn as it approaches a bystander at an intersection. According to the Doppler Effect, the bystander will notice that the sound:

• decreases in frequency

• increases in wavelength

• increases in pitch

• decreases in speed

Many movies have shown scenes where explosions can be seen and heard in outer space. Which statement BEST describes why these scenes are not correct?

• Sound waves are unable to travel in outer space.

• Light waves travel too slowly to be seen in outer space.

• Light and sound waves travel at different speeds in outer

  space.

• Light and sound waves travel in different directions in outer space.

Julia is drawing a diagram of a light ray as it enters a pane of glass. Which of these shows the correctly completed diagram?

• A

• B

• C

• D

Will the frequency of a siren become higher or lower as a police car drives away from you?

• higher

• lower

A machine converts sound into a transverse wave as shown in the diagram. If the sound becomes louder, what would the new wave look like?

• A

• B

• C

• D

How are light waves affected when they pass from one medium into a more optically dense medium at an angle different from the normal?

• The light waves bend toward the normal.

• The light waves bend away from the normal.

• The light waves continue in a straight line at constant speed.

• The light waves continue in a straight line at an accelerating speed.

Plastic lenses bend light waves making it possible for a near-sighted person to focus light onto the retina. The interaction of the light waves with the plastic lenses is known as:

• diffraction

• interference

• reflection

• refraction

Besides the wave, what else is moving to the right?

• rocks in the wave

• the wavelength

• energy of the wave

• electromagnetic waves

A system of filters gradually turns a beam of orange light (f = 5.0 × 1014 Hz) into green light (f = 6.0 × 1014 Hz). Which of the following experiences an increase during the color change?

• wavelength of the wave

• speed of the wave

• average number of photons

• average energy of the photons