PG TRB Model Question Paper for Physics with Answer - 4

Question: 16

The scientist who first discovered that the earth revolves round the sun was

(A) Copernicus 

(B) Dalton

(C) Einstein

(D) Newton

Question: 17

The molecular weight of water is

(A) 18

(B) 19

(C) 21

(D) 24

Question: 18

When X-rays are produced?

(A) heat is generated at the target

(B) the temperature of the target remains constant

(C) brilliant light is seen at the target

(D) heat is absorbed at the target

Question: 19

Temperature of the substance denotes ____ energy of its particles.

(A) Average kinetic

(B) Gravitational

(C) Potential

(D) Total

Question: 20

Ice floats on water because its density is ___ than that of water.

(A) lower

(B) higher

(C) smaller

(D) larger