Assuming the speed of sound in air equal to 340 m s^-1 and in water equal to 1360 m s^-1 , find the time taken to travel a distance 1700 m by sound in (i) air and (ii) water.

The audible frequency range of sound is :

1. 5 Hz - 10 kHz
2. 10 Hz - 20 kHz
3. 20 Hz - 20 kHz
4. 25 Hz - 40 kHz

The human ear is most sensitive in the range of …………… where it can hear a feeble sound.

1. 1000 Hz — 1500 Hz
2. 1500 Hz - 1800 Hz
3. 2000 Hz - 3000 Hz
4. 100 Hz - 500 Hz

The speed of ultrasound in air is :

1. the same as audible sound
2. less than audible sound
3. more than audible sound
4. equal to the speed of light