Work Done

Q.

A man lifts a mass of 20 kg to a height of 2.5m Assuming that the force of gravity on 1 kg mass is 10N, find the work done by the man.

Q.

Calculate the work done in bringing a unit positive test charge from a point with potential 200 V to a point at potential 100 V.

1. 50 J

2. 100 J

3. 150 J

4. 200 J

Q. A charge 'Q' is moved through a potential difference 'V'. The work done in a circuit is $W$ =

1. $\frac{V}{Q}$
2. $\frac{Q}{V}$
3. $Q\times V$

Q.

Find the work done to transfer ${10}^{19}$ charge from point A to B which is maintained at a potential difference of 5 volts.

1. 8 J

2. 10 J

3. 1 J

4. 5 J

Q.

If we have been told that

A stone weighs 2.5kg......so here is 2.5kg the mass or weight.

If it is weight then the potential energy should be equal to

Weight*height...where height is 6m

2.5kg*6m

15kgm

Q. A block of mass 5.0 kg slides down an incline of inclination 30° and length 10 m. Find the work done by the force of gravity.

Q. Work done in raising a stone of mass5kg and relative density3lying at the bed of lake through a height 5meter

Q.

A crane lifts a box of mass 400kg through a vertical height of 40m if accleration due to gravity is 9.8m/s² calculate the work done by the crane.

Q.

if 50gms be unit of mass, 60sec the unit of time and acceleration due to gravity(980cms/sec^2)be the unit of acceleration, find the new unit of energy.