Sound Test - 68...

The time period of the second hand in a clock is :

The minimum distance between the source of the sound and the obstacle for an echo (at $$20^{\circ}\,C$$) to take place is :

The time period of a vibrating body is $$ 0.02\,s $$. The frequency of the vibrating body will be 

What is the range of wavelengths of audible sound in air? (velocity of sound in air is $$340\ m/s$$)

What is the type of sound waves propagating in a solid?

Which of the following is true for sound wave?

A hospital uses an ultrasonic scanner to locate tumors in a tissue. What is the wavelength of the sound in a tissue in which the speed of the sound is $$1.7 \  km/s$$. the operating frequency of the scanner is $$4.2 \ MHz$$. ( $$1 \ MHz= 10^6 \ Hz)$$

On sending an ultrasonic wave form a ship towards the bottom of a sea, the time interval between sending the wave and receiving it back is found to be 1.5 s. If the velocity of wave in sea water is 1400 $$ms^{-1}$$ find the depth of the sea.

In a string, longitudinal wave

On a hot, dry summer day a boy is standing between plane parallel vertical cliffs separated by 75 m. He is 30 m away from one of the cliffs. Consider speed of sound in air on that hot day to be 360 m/s. The boy claps loudly and hears its successive echoes. The time in seconds at which he hears the first four echoes are respectively: