Work and Energy...

Two bodies $$A$$ and $$B$$ have masses $$20\ kg$$ and $$5\ kg$$ respectively. If they acquire the same kinetic energy. Find the ratio of thier velocities.

If increase in linear momentum of a body is 50%, then change in its kinetic energy is

A man displaces a block by $$5\ cm$$ on a rough surface $$(\mu=0.5)$$ by applying a force $$50\ N$$ acting at $$37^{o}$$ to the horizontal. The work done by the applied force is

A block of mass $$10kg$$ is moving in x-direction with a constant speed of $$10m/sec$$. It is subjected to a force $$F=-0.1x $$ Joules/meter during its travel from $$x=20$$ meters to $$x=30$$ meters. Its final kinetic energy will be-

A small solid sphere of mass $$m$$ is released from a point $$A$$ at a height $$h$$ above the bottom of a rough track as shown in the figure. If the sphere rolls down the track without slipping, its rotational kinetic energy when it comes to the bottom of track is

A worker lifts a $$20.0 kg$$ bucket of concrete from the ground up to the top of a $$20.0 m$$ tall building. What is the amount of work that the worker did in lifting the bucket?

A solid sphere of mass $$4kg$$ and radius $$1m$$ is rotating about the given axis $$xx'$$ with angular velocity $$10rad/s$$ shown in figure. The $${K.E}_{rotation}$$ is given by

The average kinetic energy of an idea gas per molecule at $$25^{o}C$$, will be

Three equal resistances each of $$10\Omega  $$ are connected. The maximum power consumed by each resistor is $$20W$$. the maximum power consumed by the system is 

Two spring of spring constant k and 3k are stretched separately by same force. The ratio of the potential energy stored in them respectively will be