Circle the best answer for each of the following questions.

1		Radio waves and x-rays are examples of
			A)	electromagnetic waves
			B)	mechanical waves
			C)	pressure waves
			D)	longitudinal waves
2		Which one of the following waves cannot travel through a vacuum?
			A)	sound waves
			B)	radio waves
			C)	light waves
			D)	x-rays
3		Which one of the following wave quantities is not related to the others?
			A)	speed
			B)	frequency
			C)	amplitude
			D)	wavelength
4		Human ears are most sensitive to sounds whose frequencies are between
			A)	10,000 and 20,000 Hz
			B)	3000 and 4000 Hz
			C)	5000 and 8000 Hz
			D)	20 and 1500 Hz
5		Two waves having the same frequency and equal amplitude A meet exactly in step at the same point. The resulting amplitude is
			A)	0.5 A
			B)	2 A
			C)	unchanged
			D)	zero
6		A violin string is bowed and at the same time is touched lightly in the middle, causing the string to vibrate in two sections. The two vibrating sections produce sound frequencies called
			A)	fundamental tones
			B)	undertones
			C)	overtones
			D)	supertones
7		If the violin string in Problem 6 was not touched and allowed to vibrate as a whole, its frequency relative to the frequencies of the two vibrating sections would be
			A)	the same
			B)	lower
			C)	higher
			D)	higher or lower depending upon the energy used to make it vibrate
8		A stationary observer hears the whistle of an approaching train. To the observer, the frequency of the sound produced by the whistle appears to be
			A)	lowest before the train reaches the observer
			B)	lowest just as the train passes the observer
			C)	the same before the train reaches the observer as after the train passes the observer
			D)	higher before the train reaches the observer and lower after the train passes the observer
9		The portion of the eye that contains the light-sensitive receptors is the
			A)	lens
			B)	cornea
			C)	pupil
			D)	retina
10		A narrow beam of white light is passed through a prism and is separated into beams of light of various colors. This is an example of
			A)	interference
			B)	dispersion
			C)	total internal reflection
			D)	resonance