Physics Questions

The working principle of a washing machine is centrifugation.

Centrifugation is a separation process which uses the action of centrifugal force to promote accelerated settling of particles in a solid-liquid mixture.

The washing machine consists of centrifuge for this purpose. A centrifuge is a piece of equipment that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis of spin that can be very strong.

Nuclear sizes are expressed in a unit called "Fermi" which is a unit of length equal to 10⁻¹⁵ metre (one femtometre), used in nuclear physics. It is similar to the diameter of a proton.

A vector quantity is a quantity which has both magnitude and direction. Here in the given options, speed is a scalar quantity but not the vector quantity.

Q and w are path functions while q+w i.e. H, enthalpy is state function. Similarly, H-TS i.e. G, Gibbs free energy is state function.

The lens which have atleast one inward curved surface is a concave lens. Concave ens is a diverging lens as it spreads out light rays that have been refracted through it.

A concave lens is thinner at its centre than at its edges.