PHYS 1305 Ch. 19 & 20 Review

On a normal day, you watch a person chopping wood and note that after the last chop you hear it 1 second later. How far away is the chopper?

• 330 m

• more than 330 m

• less than 330 m

• There's no way to tell.

You hear thunder 2 seconds after you see a lightning flash in an average temperature thunderstorm. How far away is the lightning?

• 340 m/s

• 660 m/s

• More than 660 m/s

• There's no way to tell.

Reverberations are best heard when you sing in a room with...

• carpeted walls.

• hard-surfaced walls.

• open windows.

• None of these choices.

When air near the ground on a warm day is warmed more than the air above, sound tends to bend...

• upward.

• downward.

• at right angles to the ground.

• None of these choices.

In the evening, when air directly above a pond is cooler than air above, sound across a pond tends to bend...

• upward.

• downward.

• at right angles to the ground.

• None of these choices.

Wave interference is a property of...

• sound.

• light.

• neither sound nor light.

• both sound and light.

A 1-meter-long pendulum has a bob with a mass of 1 kg. Suppose that the bob is now replaced with a different bob of mass 2 kg, how will the period of the pendulum change?

• It will double.

• It will halve.

• It will remain the same.

• There is not enough information.

A 1-meter-long pendulum has a bob with a mass of 1 kg. Suppose that the bob is now tied to a different string so that the length of the pendulum is now 2 m. How will the period of the pendulum change?

• It will increase.

• It will decrease.

• It will remain the same.

• There is not enough information!

A 1-meter-long pendulum has a bob with a mass of 1 kg. Suppose that the bob is now tied to a different string so that the length of the pendulum is now 2 m. How will the frequency of the pendulum change?

• It will increase.

• It will decrease.

• It will remain the same.

• There is not enough information!

If the frequency of a particular wave is 20 Hz, its period is:

• 1/20 second.

• 20 seconds.

• more than 20 seconds.

• None of these choices.