Which of the following force is utilized in reducing air pollution by removing dust, soot and fly-ash particles from the smoke coming out of chimneys of factories ?

Which of the following are contact forces ?

A. Friction B. Gravitational force

C. Magnetic force D. Muscular force

If we release a magnet held in our hand, it falls to the ground. The force responsible for this is :

The same force Facts on four different objects having the areas given below, one by one. In which case the pressure exerted will be the maximum?

Which of the following represent correct values for the normal atmospheric pressure?

A) 101.3 kilopascals

B) 76 mm of mercury

C) 101.3 pascals

D) 76 cm of mercury