1.The working principle of a washing machine is
A) reverse osmosis B) diffusion
C) centrifugation D) dialysis
Answer: C) centrifugation
Explanation:
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.
2.Nuclear sizes are expressed in a unit named
A) Fermi B) Angstrom
C) Newton D) Tesla
Answer: A) Fermi
Explanation:
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.
3.The speed of light will be minimum while passing through
A) water B) vaccum
C) air D) glass
Answer: D) glass
Physic test questions and answers
