Waves — Physics STD 11 Science — Question

Can the relative velocity of a moving body be zero with respect to another body? Give examples

A stone thrown vertically upward from the earth's surface, when the stone
(a) Is moving on its upward path.
(b) If it is moving in downward motion, then in which direction are its velocity and acceleration acting?

The pressure of a gas at -173°C is 1 atmosphere. Keeping the volume constant, to what temperature should the gas be heated so that its pressure becomes 2 atmosphere.

Two artificial satellites, one close to the surface and other away are revolving around the earth. Which of them has larger speed?

A spring is stretched. Is the work done by the stretching force positive or negative?

Is oscillation of a mass suspended by a spring simple harmonic in nature?

Why the speed of an object can never be negative?

In which gas, hydrogen or oxygen, will sound have greater velocity?

Which is the most accurate clock?

When 200g mass placed in a cylindrical beaker of base area 'a' is removed, the vertical length comes out of water by 2cm. What is the radius of the cylinder?