STSF1032
Part B
1. A simple harmonic oscillator consists of a 0.80kg block attached to the spring (k = 200.0
N/m). The block slides on a horizontal frictionless surface about the equilibrium point x =
0 with a total mechanical energy of 4.0 J.
(a) What is the amplitude of the oscillation?
(b) How many oscillations does the block complete in 10 s?
(c) What is the maximum kinetic energy attained by the block?
(d) What is the speed of the block at x = 0.15 m?
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STSF1032
2. A rope under a tension of 200 N and fixed at both ends, oscillates in a second harmonic
standing wave pattern. The displacement of the rope is given by
Y= (0.10m) (sin x/2) sin 12t
Where x=0 at one end of the rope, x is in meters, and t is in seconds. What are
(a) The length of the rope
(b) The speed of the waves on the rope
(c) The mass of the rope
(d) If the rope oscillates in a third harmonic standing wave pattern, what will be the
period of oscillation?
L
y(x,t) = [2Asin(kx)] Cos(wt)
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STSF1032
3. A sound source A and a reflecting surface B move directly toward each other. Relative to
the air, the speed of source A is 29.9 m/s, the speed of surface B is 65.8 m/s, and the
speed of sound is 329 m/s. The source emit wave at the frequency 1200Hz as measured
in the source frame. In the reflector frame, what are
(a) Frequency?
(b) Wavelength of the arriving sound waves?
In the source frame, what are
(c) Frequency?
(d) Wavelength of the sound waves reflected back to the source A?
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STSF1032
Hint: now treated the reflector as a source
f ' f
v  vo
v  vs
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