A microphone in the ocean is sensitive to the sounds emitted by porpoises. To produce a usable signal, sound waves striking the microphone must have an intensity of 1.02 × 10^?11 W/m2 . If porpoises emit sounds with a power of 0.049 9 W, how far away can a porpoise be and still be heard? Disregard absorption of sound waves by the water
19.7 km
You might also like to view...
RLC Circuits: What is the phase angle between the voltages of the inductor and capacitor in a RLC series circuit?
A. 0° B. 45° C. 90° D. 180° E. 270°
Consider a large molecular cloud that will give birth to a cluster of stars. Which of the following would you expect to be true?
A) A few massive stars will form, live, and die before the majority of the star's clusters even complete their protostar stage. B) All the stars in the cluster will be of about the same mass. C) All the stars in the cluster will become main-sequence stars at about the same time. D) All the stars in the cluster will have approximately the same luminosity and surface temperature.
An electric motor on an airplane operates on 24 volts and draws a current of 15 amperes. (a) What is the power consumption of the motor? (b) How much energy does the motor use during a 2 hour flight?
The stress that occurs when material is pulled apart is called
A) compressional stress. B) tensional stress. C) shear stress. D) simple stress.