निम्नलिखित में सही

What is the frequency of Ultrasonic Waves?

Velocity of the sound is minimum in-

‘Therm' is the unit of –

Which of the following is the time taken for one complete oscillation of a sound wave in the density of the medium?

The momentum of a body depends on:

Which physical property causes raindrops to form spherical shapes?

Heat stored in water vapour is –

Which statement about Cathode Rays is incorrect ?

The hair of shaving brush clings together when removed from water due to –

Which atmospheric layer contains ozone layer?