Q1.

By what factor will an intensity change when the corresponding sound level increases by 4.6 dB?

Q2.

By what factor is the intensity of sound at a rock concert louder than that of a whisper when the two intensity levels are 120 dB and 20 dB respectively?

Q3.

A point source emits sound with a power output of 192 watts. What is the intensity (in milli-watt/m²) at a distance of 13.1m from the source?

Q4.

A point source emits sound waves with a power output of 38watts. What is the sound level (in dB) at a distance of 14 m?

Q5.

A car approaches a stationary police car at 31 m/s. The frequency of the siren at its source is 506 Hz. What is the frequency (in Hz) heard by an observer in the moving car as he approaches the police car? (Assume the velocity of sound in air is 343 m/s.)