A lift is moving down with acceleration a. A man in the lift drops a ball inside the lift. The acceleration of the ball as observed by the man in the lift and a man standing stationary on the ground are respectively :
A child swinging on a swing in sitting position, stands up, then what will be the time period of the swing?
Two identical particles move towards each other with velocity 2v and v respectively. The velocity of centre of mass is :
Wavelength of light used in an optical instrument are then ratio of their respective resolving powers (corresponding to ) is:
A charged particle q is placed at the centre O of cube of length L (ABCDEPGH). Another same .charge q is placed at a distance L from O. Then the electric flux through ABCD is :
If a spring has time period T, and is cut into n equal parts, then the time period of each part will be :