Work and Energy...

An elevator is run by the cables at constant speed. The total work done by the elevator is:

Kinetic energy of the liquid per unit mass is

An energy of $$4 kJ$$ causes a displacement of $$64 m$$ in $$2.5 s$$. The power delivered is

 Work done in lifting a body is calculated by

A stone is projected vertically up to reach maximum height $$h$$. The ratio of its kinetic to potential energies at a height $$\cfrac{4h}{5}$$ will be

Two masses $$10 \ gm$$ and $$40 \ gm$$ are moving with kinetic energies in the ratio $$9:25$$. The ratio of their linear momentum is:

When the mass of body is halved and velocity is doubled, then the kinetic energy of the body 

Mass of $$B$$ is four times that of $$A . B$$ moves with a velocity half that of $$A$$. Then, $$B$$ has 

A body of mass $$15\ kg$$ moving with a velocity of $$10\ ms^{-1}$$ is bought to rest. The work done by the brake is

If the unit of force and length each be increased by four times, then the unit of energy is increased by