List of top Physics Questions asked in OJEE

Unit of power is :
SI unit of force is :
Which Instrument measures electric current?
Speed of Light in vacuum is :
Work done=?
In a mechanical refrigeration system, the highest temperature of refrigerant occurs
A self-locking screw is one which
A point charge +q is placed precisely at the center of one of the faces of a perfectly symmetrical cube. What is the total electric flux passing through the cube?
Five equal point charges, each +q, are placed at five of the six vertices of a regular hexagon of side length a. What is the magnitude of the electric field at the center of the hexagon?
Two identical conducting spheres, one carrying a charge of +4q and the other carrying -2q, are kept at a distance r apart in a vacuum. The magnitude of the electrostatic force between them is F. If they are brought into contact and then separated to the same distance r, what is the new electrostatic force between them?
A charge Q is placed at the center of an uncharged, hollow, conducting spherical shell. What is the electric field at a point outside the shell at a distance r from the center, and what is the net charge on the outer surface of the shell?
A simple pendulum has a bob of mass m carrying a positive charge q. It is placed in a region where a uniform electric field E is directed vertically upwards. If the string is displaced slightly and released, what happens to its time period T compared to its time period T$_0$ without the electric field?