Advertisements
Advertisements
प्रश्न
In which of the following cases, is work being done?
(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
Advertisements
उत्तर
Work is done only in case of a boy climbing up a stair case.
संबंधित प्रश्न
Give one example each in which a force does (a) positive work (b) negative work, and (c) zero work.
When is the work done by a force on a body : (a) positive, (b) negative, and (c) zero?
If the work done by a force in moving an object through a distance of 20 cm is 24.2 J, what is the magnitude of the force?
How much work is done by the gravitational force of earth acting on a satellite moving around it in a circular path? Give reason for your answer.
A uniform circular motion is an accelerated motion. Justify it.
Name the type of energy possessed by a
(i) stretched catapult (ii) hot iron
(iii) wound up clock
Name two places in India where electricity is generated from nuclear power plants.
Explain, why submarines are able to dive underwater as well as a sail on the surface of the water?
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 |
