Which of the following is NOT true about mechanical waves?

• They carry energy

• They transfer matter

• They can be longitudinal

• They require a medium

In a transverse wave, the medium vibrates

• at right angles to the wave direction

• in the same direction as the wave

• in a direction opposite that of the wave

• at a 45 degree angle to the wave direction

The height of a wave crest is called

• wavelength

• frequency

• amplitude

• energy

For waves moving at a constant speed, if wavelength is doubled, then frequency is

• doubled

• halved

• unchanged

• quadrupled

When a wave is reflected, its speed

• increases

• decreases

• increases or decreases

• is unchanged

When a wave bends around an obstacle, it is called

• reflection

• refraction

• diffraction

• interference

When two waves interfere, the displacement where two troughs meet is

• positive

• negative

• zero

• a crest

A large speaker is better than a small speaker for producing sounds with

• low frequency

• high frequency

• low intensity

• high intensity

The highest-frequency sound human ears can usually hear is about

• 20 Hz

• 10,000 Hz

• 20,000 Hz

• 30,000 Hz

Sonar can make use of

• the Doppler effect

• infrasound

• ultrasound

• resonance