waves

Question 1

The graph below shows an oscillator undergoing Simple Harmonic Motion. Which point(s) on the graph corresponds to the oscillator having zero speed? (Click all that apply)

Answer 1

2, 4

Question 2

A mass is bobbing up and down on a spring. If you increase the amplitude of the motion, how does this affect the time for one oscillation?

Answer 2

the time does not change

Question 3

A mass on a spring in SHM has amplitude A and period T. How long does it take for the mass to travel a total distance of 8A?

Answer 3

2T

Question 4

Consider a wave on a string moving to the right, as shown below. What is the direction of the velocity of a particle at the point labeled B?

Answer 4

upward

Question 5

What is the wave speed of the wave traveling on the string? Give your answer in m/s, but do not include units with your response. Figure 1. Wave on a String at a fixed time t = 0 s. Figure 2. Wave on a String at a fixed position x = 0 m

Answer 5

v = wavelength/ period = 5m/2s = 2.5m/s

Question 6

What might this be?

Answer 6

An Aeolian harp

Question 7

The length of the string is 2.0 m. Approximately what is the wavelength of the two traveling waves that make up the standing wave?

Answer 7

wavelength/ # of loops = 2L/n / 5 = 0.4 m

Question 8

A string of length 2.0 m has a mass of 125 mg. The string is attached to the ceiling and a large rock of mass 4.0 kg hangs from the other end. The rock is hit sideways with as a result, a transverse pulse travels up the string toward the ceiling. At what speed does the pulse travel?

Answer 8

790 m/s

Question 9

A string is attached to a vibrator driven at 1.20 × 102 Hz. A weight hangs from the other end of the string; the weight is adjusted until a standing wave is formed. If the weight of the mass is 0.3 N and the linear density of the string is 0.01 Kg/m. What is the wavelength of the standing wave on the string? (It’s a real long string)

Answer 9

22 m

Question 10

Resonance is from a Latin noun that means

Answer 10

an echo

Question 11

Compared to sound frequency, earthquake frequencies are

Answer 11

much lower

Question 12

If the frequency of an earthquake is 4 Hz, and the wavelength is 1500 m, what is the speed of the earthquake?

Answer 12

4 * 1500 = 6000 m/s

Question 13

Sound waves are

Answer 13

-longitudinal waves characterized by the displacement of air molecules.
-longitudinal waves characterized by pressure differences.

Question 14

Calculate the speed of sound at 10o C,

Answer 14

331.5 + (0.6 * 10) = 337.5 m/s

Question 15

You have two tuning forks, one with a frequency of 235 Hz, and a second with a frequency of 236 Hz. If you hit them both at the same time, what is the beat frequency heard?

Answer 15

1 Hz

Question 16

If the speed of sound in water is 767m/s. Caclulate the wavelength of a sound wave in water that has a frequency of 440 Hz (That’s an A) The answer should be in meters, do include the m

Answer 16

1.74m

Question 17

A single cricket in a field is chirping at a sound level of 30 dB. What is the resulting sound level if 100 similar crickets make a chorus of chirping? Give your answer in dB.

Answer 17

I100/I1=100
β2−β1=10dB∗log(I2/I1)
β100−β1=10dB∗log(I100/I1)=10dB∗log(100)=20dB

50dB (Answer)

Question 18

Every vibration gives the sound box a push. A frequency of 256 pushes per second is

Answer 18

middle C

Question 19

Which of the following best describes a sound level of intensity 0.0001 W/m2?

Answer 19

about that of a power mower

Question 20

What is the approximate decibel level of a jet engine from 30 meters?

Answer 20

110 dB