Physics

Optical center is a point on the main axis of a lens that is so located that any ray of light passing through it suffers no deviation.

Magnification refers to how much larger the image is than the real object. If the length of an object is l and the length of its image is l′, then magnification is – m = l′/l

A plane mirror is a plane and smooth surface on which regular reflection of light takes place.

The area of influence created by a charged object is said to be that object’s electric field.

Simple harmonic motion is a special type of periodic motion or oscillation where the restoring force is directly proportional to the displacement and acts in the direction opposite to that of displacement.

The force that causes the radiation of Beta(β) rays from the radioactive nucleus is called weak nuclear force. The radius of action of this force is 10-15 m.

The number of complete waves produced in one second is called the frequency of the wave.

If one-ampere current flows for one second, the amount of charge that flows is called one coulomb (C).