A car of mass '$$m$$' moving with velocity '$$u$$' on a straight road in a straight line, doubles its velocity in time t. The power delivered by the engine of a car for doubling the velocity is

A bob of a simple pendulum of mass 'm' is displaced through 90$$^\circ$$ from mean position and released. When the bob is at lowest position, the tension in the string is

Three bodies P, Q and R have masses 'm' kg, '2m' kg and '3m' kg respectively. If all the bodies have equal kinetic energy, then greater momentum will be for body/bodies.

A sphere of mass 25 gram is placed on a vertical spring. It is compressed by $$0.2 \mathrm{~m}$$ using a force $$5 \mathrm{~N}$$. When the spring is released, the sphere will reach a height of $$\left(\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2\right)$$ $$2 \mathrm{~m}$$