Work and Energy

Work is done on a body when

• force acts on the body but not displaced

• force does not act on the body but it is displaced

• force acts on the body perpendicular to the direction of displacement of body

• force act on a body and the displacement is in direction of force or opposite to direction of force

The work done on an object does NOT depend upon the

• force applied

• initial velocity of body

• displacement

• angle between force and displacement

In case of negative work, the angel between force and displacement is

• 0 degree

• 45 degree

• 90 degree

• 180 degree

In a tug of war, work done by a winning body is

• zero

• positive

• negative

• none of these

In a tug of war, work done by losing team is

• zero

• positive

• negative

• none of these

A force of 100N on a body does 1000J of work. The distance through which the body is displaced is

• 5m

• 10 cm

• 10 m

• 5cm

S.I. unit of energy is

• erg

• dyne

• joule

• newton

Water stored in a dam possesses

• Kinetic energy

• Potential energy

• Electric energy

• no energy

Potential energy of a stretched string is

• Gravitational P.E.

• Plastic P.E.

• Elastic P.E.

• None of these

When electric current passes through an electric bulb, electric energy is converted to

• Heat energy only

• light energy only

• both heat and light energy

• both light and chemical energy