The weight of a body in air 40N. When the body immersed in water the weight 20N and if the body immersed in unknown liquid the weight 30N. What is density of liquid?

The weight of a body of mass 1 kg

What is weight of a body?

The weight of a body is different in different places. Why?

When a body is fully or partly immersed in a liquid, name the forces acting on the body.

A converging lens has focal length of 20 cm in air. It is made of a material of refractive index 1.6. If it is immersed in a liquid of refractive index 1.3, what will be its new focal length?

A rope of negligible mass is wound round a hollow cylfnder of mass 3 kg and radius 40 cm. What is the angular acceleration of the cylinder if the rope is pulled with a force of 30 N? What is the linear acceleration of the rope? Assume that there is no slipping.

A body age of mass 50 kilogram, what is his weight?

A convex lens of focal length 24 cm is totally immersed in water (n = 1.33). Find its focal length in water (n = 1.5).