Waves Practice Problem Set Worksheet Page 9
ADVERTISEMENT
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47M
P
P
S
6
ECHANICS
RACTICE
ROBLEM
ETS
7.4
SHM & S
R
OUND
EVIEW
7.4.1 Sound
1. (G11.35) A sound wave in air has a frequency of 262 Hz and travels at a speed of 330
m/s. How far apart are the wave crests (compressions)? Answer: 1.26 m
2. (G11.37) Calculate the speed of longitudinal waves in:
3
a. Water
Answer: 1.4 x 10
m/s
3
b. Granite
Answer: 4.1 x 10
m/s
3
c. Steel
Answer: 5.1 x 10
m/s
3. (G11.39) A cord of mass 0.55 kg is stretched between two supports 30 m apart. If the
tension in the cord is 150 N, how long will it take a pulse to travel from one support
to the other?
Answer: 0.33 sec
4. (G11.41) A sailor strikes the side of his ship just below the surface of the sea. He
hears the echo of the wave reflected from the ocean floor directly below 3.0 s later.
How deep is the ocean at this point?
Answer: 2.3 km
5. (G12.1) A hiker determines the length of a lake by listening for the echo of her shout
reflected by the cliff at the far end of the lake. She hears the echo 1.5 s after shouting.
2
Estimate the length of the lake.
Answer: 2.6 x 10
m
6. (G12.5) A person sees a heavy stone strike the concrete pavement. A moment later
two sounds are heard from the impact: one travels in the air and the other in the
concrete, and they are 1.4 sec apart. How far away did the impact occur?
2
Answer: 5.4 x 10
m
7. (G12.6) A fishing boat is drifting just above a school of tuna on a foggy day. Without
warning, an engine backfire occurs on another boat 1.0 km away. How much time
elapses between the instant when the backfire is heard…
a. by the fish?
Answer: 0.69 sec
b. by the fishermen?
Answer: 2.9 sec
8. (G12.7) The sound from a very high burst of fireworks takes 4.5 s to arrive at your
eardrums. The burst occurred 1500 m above you and traveled vertically through two
stratified layers of air, the top one at 0°C and the bottom one at 20°C. How thick is
each layer of air?
Answer: 1200 m, 300 m
9. (G12.43) What will be the “beat frequency” if middle C (262 Hz) and C# (277 Hz)
are played together?
Answer: 15 Hz
a. What if each was played two octaves lower (each frequency reduced by a
factor of 4)
Answer: 3.8 Hz
Gamzon & Gregorian-Michaelsen
6/7/16
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education