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प्रश्न
Define work.
Define the term work
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उत्तर
The work done by a force on a body is equal to the product of the force applied and the distance moved by the body in the direction of force i.e.,
Work done = Force × distance moved in the direction of force
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संबंधित प्रश्न
Soni says that the acceleration in an object could be zero even when several forces are acting on it. Do you agree with her? Why?
In which of the following cases is work being done:
- A boy pushing a heavy rock
- A boy climbing up the stairs
- A coolie standing with a box on his head
- A girl moving on the road.
The moon is revolving around the earth in a circular path. How much work is done by the moon?
Define 1 joule of energy.
Give reasons for the following A teacher moving around in the class is doing work but a child standing and reading a book is not doing any work.
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.
A weight lifter lifted a load of 200 kgf to a height of 2.5 m in 5 s. Calculate:
- the work done, and
- the power developed by him. Take g = 10 N kg-1
How much work is done when a body of mass m is raised to a height h above the ground?
How much work is done when a force of 2 N moves a body through a distance of 10 cm in the direction of force?
What should be the angle between the direction of force and the direction of motion of a body so that the work done is zero?
Ravi applied a force of 10 N and moved a book 30 cm in the direction of the force. How much was the work done by Ravi?
Name the CGS unit of work.
A boy pulls a box up to 10 m with a force of 5 kgf. Calculate the work done by him.
How fast should a boy weighting 30 kg run so that his kinetic energy is 375 joule?
What do you understand by 'potential energy' and 'Kinetic energy'? Give three examples of each to illustrate your answer.
Fill in the boxe to show the corresponding energy transformation.
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.
Is power a scalar or a vector quantity?
What do you understand by the term energy? Is energy a scalar or vector? How is the energy possessed by a body measured?
What is the difference between renewable and non-renewable resources?
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 |
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A wind-mill is lifting water from a well.
A body of mass 0.5 kg travels on straight line path with velocity v = (3x2 + 4) m/s. The net work done by the force during its displacement from x = 0 tox = 2 m is ______.
State whether work is done or not, by writing yes or no, in the following case:
A man pushes a wall.
