S_(1) and S_(2) are two loudspeakers with the same frequency of 165 Hz and acoustic output 1.2 xx 10^(-3) and 1.8 xx 10^(-3) watt respectively. They vibrate in the same phase. P is a point at a distance 4 m from S_(1) and 3 m from S_(2). (a) How are the phases of the two waves arriving at P related ? (b) What is the intensity of P if S_(1) is turned off (S_(2) " on")? (c) What is the intensity of sound at P if S_(2) is turmed off ? (d) What is the intensity at P with S_(1) and S_(2) on ? [Hint : For phase relationship see example 6 of chapter 1. Intensity is inversely proportional to square of the distance]

S_(1) and S_(2) are two loudspeakers with the same frequency of 165 Hz

1.	S_(1) and S_(2) are two loudspeakers with the same frequency of 165 Hz and acoustic output 1.2 xx 10^(-3) and 1.8 xx 10^(-3) watt respectively. They vibrate in the same phase. P is a point at a distance 4 m from S_(1) and 3 m from S_(2). (a) How are the phases of the two waves arriving at P related ? (b) What is the intensity of P if S_(1) is turned off (S_(2) " on")? (c) What is the intensity of sound at P if S_(2) is turmed off ? (d) What is the intensity at P with S_(1) and S_(2) on ? [Hint : For phase relationship see example 6 of chapter 1. Intensity is inversely proportional to square of the distance]
Answer» Answer :(a) `PI`, (b) `0.2 XX 10^(-3) W` (c) `0.075 xx 10^(-3)` , (d) `0.03 xx 10^(-3)W`