Advertisements
Advertisements
Question
Solution
APPEARS IN
RELATED QUESTIONS
A force of 7 N acts on an object. The displacement is, say 8 m, in the direction of the force (see the given figure). Let us take it that the force acts on the object through the displacement. What is the work done in this case?
Define work.
State two conditions when no work is done by a force.
A body, when acted upon by a force of 10 kgf, moves to a distance 0.5 m in the direction of force. Find the work done by the force. Take 1 kgf = 10 N.
Differentiate between energy and power.
State two disadvantages of producing hydroelectricity.
What are the units of (a) work, and (b) energy?
A force of 50 N acts on a body and moves it a distance of 4 m on horizontal surface. Calculate the work done if the direction of force is at an angle of 60° to the horizontal surface.
Name the physical quantity whose SI unit is Nm.
Nm is the unit of .......
Is work done a scalar or a vector physical quantity?
What do you mean by a kilo joule?
No work is done by a man moving on a horizontal road while carrying a box on his head. Explain.
A weight lifted a load of 200 kgf to a height of 2.5 m in 5 s. calculate: (i) the work done, and (ii) the power developed by him. Take g= 10 N kg-1.
A cricket ball is thrown up from the earth's surface. What happens to its P.E.
(a) during the motion
(b) at the highest point?
Name the physical quantity associated with the 'rate of doing work'.
A woman pulls a bucket of water of total mass 5 kg from a well which is 10 s. calculate the power used by her.
State the energy changes which take place when A piece of magnesium wire is burnt in a jar of oxygen.
Mention whether work is done or not in the following activity.
| S. No | Activity | Work done or not done |
| 1. | Pushing the door | |
| 2. | Holding a doll | |
| 3. | Sitting in a bus | |
| 4. | Pushing a wall | |
| 5. | Digging soil |
