Review: Units Eleven and Twelve
Physics
Review: Units Eleven and Twelve
1) (1 point) Define simple harmonic motion. Give an example of periodic motion that is harmonic and one that is not.
2) (2) A spring hooked to the ceiling bounces up and down. Describe its acceleration, and compare its velocity at the bottom, middle, and top of its cycle.
3) (3) A spring with a spring constant of 13 N/m is hooked to the ceiling. When a mass is attached to it, the spring stretches 0.30 m. a) How big is the mass, and b) what will be the frequency of oscillations?
4) (1) If you double the length of a pendulum, by how much will its period change? (If you’re not sure, make up two pendulums and compare them.)
5) (2) Sketch a transverse and a longitudinal wave. Label the compressions, troughs, wavelengths, crests, amplitudes, and rarefactions.
6) (1) Describe how a longitudinal wave can be represented by a transverse wave.
7) (1) A periodic wave has a wavelength of 0.50 m and a speed of 20 m/s. What is the frequency?
8) (1) Sketch an example of complete constructive interference of two waves. Sketch another example of partial destructive interference of two waves.
9) (1) Consider two identical wave pulses on a rope. Suppose the first pulse reaches the fixed end of the rope, is reflected back, and then meets the second pulse. When the two pulses overlap exactly, the superposition principle predicts that the amplitude of the resultant pulses at that moment will be what factor times the amplitude of one of the original pulses?
10) (1) A 2.0 m long stretched rope is fixed at both ends. Which wavelength would NOT produce standing waves on this rope?
a. / 2.0 m / c. / 4.0 mb. / 3.0 m / d. / 6.0 m
11) (1) Amplitude is to volume as frequency is to ______.
12) (1) Which of the following has the highest speed of sound?
a. / helium at 0°C / c. / copper at 0Cb. / air at 0C / d. / air at 100C
13) (2) What is the Doppler effect. Give an example. Now give an example of how it might manifest in a wave that isn’t sound.
14) (2) What is the intensity of sound waves produced by a trumpet at a distance of 1.6 m when the power output of the trumpet is 0.30 W?
a. / 5.9 10–3 W/m2 / c. / 9.4 10–3 W/m2b. / 1.5 10–2 W/m2 / d. / 3.7 10–2 W/m2
15) (2) If the intensity of a sound is increased by a factor of 100, by how much will the decibel level increase? How much louder is the sound?
16) (2) What are the first two sound frequencies that will be created by a 0.25 m flute that is closed at one end assuming the speed of sound is 343 m/s?
17) (1) Define timbre. What creates different timbres?
18) (1) What are beats, and how are they useful? Give an example of their use (be sure to include numerical values in your example).
Total points: 26