# Work And Energy

## The relation between the escape velocity V esc and orbital speed Vo is given by

A.V esc = 1/2Vo B.V esc = ?2 Vo C.V esc = Vo D.V esc = 2Vo

## The escape velocity form the earth surface in km S-1 is

A.4.2 km S-1 B.7.5 km S-1 C.9.5 km S-1 D.1.1 km S-1

## If moon radius is 1600 km and g on its surface is 1.6 ms-2 then the escape velocity on the moon is

A.1600 ms-1 B.50.6 ms-1 C.71.6 ms-1 D.2263ms-1

## When two protons are brought together

A.Kinetic energy increases B.P.E. between them increases C.P.E. between them decreases D.P.E. between tem does not change

## When arrow is released form its bow, its energy is transformed from

A.heat energy to K.E B.elastic P.E to K.E C.elemical energy to elastic P.E D.K.E to elastic P.E.

## A man lifts vertically a weight of 40kg through 1m in 10s; while a chile lifts vertically a weight of 10kg through a distance of 1m in 1s. What will be correct inference?

A.man does more work than child B.child does more work than man C.both do the same amount of work D.it is a foolish question

## The work done by friction is

A.positive B.negative C.zero D.none of these

## The area under the force displacement graph represents

A.area B.work done C.power D.none of these

## The dimension of power is

A.[ML2T-3] B.[ML2T-2] C.[ML2T3] D.none of these

## Propulsion force of a rocket is

A.non-conservative force B.conservative force C.both (a) and (b) D.non of these