Think you’ve got your head wrapped around Waves? Put your knowledge to
the test. Good luck — the Stickman is counting on you!
Q. An LP record spins on turntables at 33.33 rpm. What is its angular frequency?
0.09 rad/s
0.18 rad/s
0.56 rad/s
1.75 rad/s
3.49 rad/s
Q. A 0.5 kg block connected to a spring with a stiffness of 10 N/m slides back and forth on a frictionless table. At t = 0 the block starts at the fully extended position of the spring, 2 cm away from equilibrium. What is its position relative to equilibrium at t = 5 s? Recall the frequency of a block-spring system is 
.
. -1.85 cm (spring compressed)
-1.28 cm (spring compressed)
-0.93 cm (spring compressed)
0.93 cm (spring extended)
1.85 cm (spring extended)
Q. For the spring-block system in the previous question, which of the spring stiffnesses below would place the block back at equilibrium at t = π s?
2π N/m
9.875 N/m
10.125 N/m
(10 + π) N/m
20 N/m
Q. What is the period of a wave that oscillates at 20 rad/s?
0.008 s
0.050 s
0.100 s
0.157 s
0.314 s
Q. Which of the following is an example of a longitudinal wave?
"the wave" at a crowded stadium
a plucked guitar string
a crawling caterpillar
human speech
the light from an incandescent bulb
Q. What is the wavelength of blue light (f = 650×1012 Hz)?
73.5 nm
462 nm
650 nm
1450 nm
2900 nm
Q. The wave below interferes with another wave to produce the pictured resultant waveform. Which of these waves did it interfere with? 
Q. If two waves have the same frequency and amplitude, how many radians out of phase with one another do they have to be in order to destructively interfere such that the wave disappears entirely?
0 rad
π rad
2π rad
Q. Sound travels much faster in seawater than in air—around 1560 m/s in the ocean. If a submarine engine humming at 100 Hz was to motor past you at 10 m/s faster than you as you swam underwater, what frequency would you hear approaching?
99.36 Hz
100.00 Hz
100.65 Hz
103.03 Hz
127.87 Hz
Q. How fast would a plane have to travel in order to shift its 400 Hz engine hum up an entire octave, doubling the sound's frequency as the plane approaches you?
85 m/s
170 m/s
340 m/s
400 m/s
680 m/s