Physics

Nuclear sizes are expressed in a unit called “Fermi” which is a unit of length equal to 1015 metre(one femtometre), used in nuclear physics.

During hot weather, the fan produces a feeling of comfort. This is because our perspiration evaporates rapidly.

Transition metal ions have an incomplete set of 3d electrons. Changes in the energy of these electrons correspond to the energy of visible light. The absorption of visible light by these ions lend colour to gems.

Angle of friction and angle of repose are equal to each other.

An adiabatic process is one that occurs without transfer of heat or matter between a thermodynamic system and its surroundings. In an adiabatic process, energy is transferred only as work._x000D_ Rarefaction is the reduction of an item’s density, the opposite of compression.

Conduction is the transfer of heat between substances that are in direct contact with each other. Conduction occurs when a substance is heated, particles will gain more energy, and vibrate more. These molecules then bump into nearby particles and transfer some of their energy to them.

Intensity of sound at a point is its distance from the source.

When a metal plate with a circular hole at its centre is heated, definitely along with the areal expansion of the plate the diameter (sum of two radii) of the circular hole also increases.

Newton’s third law states that “For every action, there is an equal and opposite reaction.” The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. So harder the stone is kicked, the harder will be its effect on the hitter.