Can any object have mechanical energy if its momentum is zero? Explain.

Can an object have more than one centre of gravity?

Magnetic field arises due to charges in motion. Can a system have magnetic moments even though its net charge is zero ? Explain.

Explain : Plants have low energy needs.

Suppose you are in a dark room . Can you see objects in the room ?Can you see objects outside the room ? Explain.

Can a disease be detected before its symptoms appear? Explain the principle involved.

If the uncertainty in the positioin of an electron is zero, the uncertainty in its momentum would be