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प्रश्न
When is work said to be done by a force?
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उत्तर
Work is said to be done when a force moves an object through a distance in its own direction.
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संबंधित प्रश्न
Name six simple machines. Give an example of each machine.
Give two examples of inclined plane where it is used to raise a heavy load with less effort ?
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(i) Draw a string around the pulleys. Also show the place and direction in which the effort is applied.
(ii) What is the velocity ratio of the system?
(iii) What is the mechanical advantage of the system?
(iv) What assumption do you make in arriving at your answer in part (iii)?
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To lift bricks to the top of a tall building.
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| ______ | ______ | _______ |
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| ______ | ______ | ______ |
Name a machine for each of the following uses:
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- to change the point of application of force,
- to change the direction of force,
- to obtain the gain in speed.
