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प्रश्न
Classify the following as a lever, a pulley and an inclined plane:
A needle
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उत्तर
A needle – An inclined plane
संबंधित प्रश्न
State whether the following statement is True or False.
A boy does work while pushing a wall.
State whether the following statement is True or False.
In an ideal machine, work done on load is equal to the work done by effort.
Fig show a system of four pulleys. The upper two pulleys are fixed and the lower two are movable.
(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)?
Define mechanical advantage (M.A.) of the machine.
What is the relationship between the mechanical advantage and the velocity ratio for:
(i) An ideal machine,
(ii) A practical machine.
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To lift bricks to the top of a tall building.
Name the levers mentioned in the following passage. Identify the fulcrum, load, and effort of each and say which type of lever it is.
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