Quiz: The Behavior of Mechanical Waves

What property of a sound wave is a sound's volume related to?

• period

• frequency

• amplitude

• wavelength

Which property of a sound wave is related to the pitch of the sound?

• period

• frequency

• amplitude

• wavelength

Through which of these media do sound waves travel most slowly?

• air

• iron

• wood

• water

When a mechanical wave travels from its source, the wave's energy decreases. Why?

• period decreases

• amplitude decreases

• frequency decreases

• wavelength decreases

The diagram shows possible paths of mechanical waves from the source of an earthquake. The waves change speed, direction, and shape as they move through the different materials that make up Earth. Assume that the four labeled waves all have the same energy when they leave the earthquake source. Which wave has the least effect on Earth’s surface?

• wave 1

• wave 2

• wave 3

• wave 4

Four different waves, A, B, C, and D are moving through a medium. A has the greatest frequency, followed by B, C, then D. Which of these waves will lose the most energy when passing through the medium?

• A

• B

• C

• D

A mechanical wave is traveling through medium A. When the wave enters medium B, it speeds up. Which of these statements could be true about medium A and medium B?

• Medium A is a solid and medium B is a gas.

• Medium A is a liquid and medium B is a solid.

• Medium A is a gas and medium B is a vacuum.

• Medium A is a vacuum and medium B is a liquid.

What happens when a mechanical wave encounters a boundary between two different media?

• The wave is completely absorbed.

• The wave is completely reflected.

• The wave is partially reflected and partially transmitted.

• The wave stops moving.

When a mechanical wave is partially reflected and partially transmitted, it becomes two waves. What happens to the energies and amplitudes of the two waves?

• The energy is equally divided, and amplitudes remain the same.

• The energy is divided based on the reflection and transmission coefficients, and amplitudes change accordingly.

• The energy is lost, and amplitudes decrease.

• The energy is conserved, and amplitudes increase.

Earthquakes are more intense near the initial disturbance than they are farther away because:

• the energy is concentrated at the epicenter.

• the seismic waves lose energy as they travel.

• the ground is softer near the epicenter.

• the tectonic plates are thicker near the epicenter.