Acoustics Answers

A grade-school teacher insists that the the overall sound level in his classroom not exceed 64 dB at his location. There are 25 students in his class. If each student talks at the same intensity level, and they all talk at once, what is the highest sound level at which each one can talk without exceeding the limit? answer in Db(decibels)

Jane and Sam alternately pound a railroad spike into a tie with their hammers. The crew chief has a migraine, and notes that Jane's hammer blows cause a sound with intensity 5.0 times greater than the sound that Sam makes when he swings his hammer. What is the difference in sound level between the two sounds? answer in dB(decibels)

The sound of heavy automobile traffic, heard at a certain distance, has a sound level of about 75 dB. What is the intensity of the noise there? answer in W/m^2.

A wave travels down a zinc slinky with 1" coils. The wavelength is .5m. What is the frequency? Find the period.

A standing wave had a 1st fundamental frequency of 13 Hz. What would be the frequency of the 3rd harmonic?

A locomotive engine passes a stationary observer at a speed of 72 km/h emitting a note of frequency 500 Hz. Calculate the frequency of sound heard by the observer
(i) before, and

(ii) after the engine passes the observer.
The speed of sound in air is 340 m/s.

What is the resonanse? ANSWER PLEASE !!!

a stone is dropped from a cliff onto a flowing river below. if it takes the stone 0.185 minutes to hit the water, how high is the cliff?

Which charge is two opposite electrical charges will double the force of their attraction to one another?


a. halving the distance separating them
b. doubling the distance separating them
c. doubling one charge
d. doubling both charges

A block with a speaker bolted to it is connected to a spring having spring constant k = 20.0 N/m as in Figure 3. The total mass of the block and speaker is 5.00 kg, and the amplitude of this unit’s motion is 0.500 m. If the speaker emits sound waves of frequency 440 Hz, determine the range in frequencies heard by the person to the right of the speaker.