Question

(a) Sound is produced when your school bell is struck with a hammer. Why? (b) Wch characteristic of sound helps to identify your friend by s voice wle sitting with others in a dark room?

Answer 1

because the air particles which are relax got active and struck so the sound ia produced .
sound does not need straight medium to travel and it also travel more fastly where nothing is present

Answer 2

☆$\red {HELLO\:DEAR}$☆

Quality of sound is that characteristic which helps us identify a particular person.

Sound produced by two persons may have the same pitch and loudness, but the quality of the two sounds will be different.

☆$\green {VISHU\:PANDAT}$☆

☆$\blue {FOLLOW\:ME}$☆