Advertisements
Advertisements
प्रश्न
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 |
Advertisements
उत्तर
| S. No | Activity | Work done or not done |
| 1. | Pushing the door | Work done |
| 2. | Holding a doll | Not done |
| 3. | Sitting in a bus | Not done |
| 4. | Pushing a wall | Not done |
| 5. | Digging soil | Work done |
APPEARS IN
संबंधित प्रश्न
Name a common device where a gear train is used
Give reasons for the following. No work is done if a man is pushing against a wall.
A boy of mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate:
- the force of gravity acting on the boy,
- the work done by him against the force of gravity,
- the power spent by boy. (Take g = 10 m s-2)
Is the motion of moon around the earth in circular path an accelerated motion?
How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?
A girl of mass 50 kg runs up a flight of 40 steps in 20 seconds. If each step in 20 cm high, calculate the power developed by the girl. (g= 10 ms-2).
State the energy changes which take place when An electric bulb glows when it is connected to a source of electric current.
In the following case write yes, if the work is being done and no if no work is being done.
A boy climbing up a staircase.
One labourer carried four pans of road metal through a distance of 100 metres. If he carries two pans of road metal through a 200 metre distance ______ work will be done.
