Question

3. Sound a) (5 pts) True or False? i Sound wave does not require a medium to propagate. ii. If the frequency of a sound wave is increased the speed of the sound will increase. iii. The loudness of the sound you hear goes up and down with a regular frequency when there are two sound sources of frequencies that are close but not equal to each other. iv. The fundamental frequency of a tuba is 36 Hz. Considering a tuba to be a resonant tube with one end open the next higher frequency of sound the tuba generates is 72 Hz. v. When a standing wave is formed on a string fixed at the two ends there are some spots on the string which do not move at all.

Answer 1

Answer : i ) False, medium is necessary to propagate sound waves.

ii ) False, we know that velocity of sound depends on the properties of the medium,not depend on frequency.

iii ) False, loudness is directly proportional to amplitude of sound wave.

iv ) False , given problem tuba to be resonating tube with one end open means it acts as closed pipe. The frequency ratio of the closed pipe is 1:3:5.....only odd harmonics are possible.

v ) True, In standing waves are formed due to superposition of two sound waves in opposite direction.At node points particles do not move at all.