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Question
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
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Solution
It is used only to change the direction of effort to a more convenient direction and to use one’s own weight for the effort.
RELATED QUESTIONS
A boy uses a single fixed pulley to lift a load of 50 kgf to some height. Another boy uses a single movable pulley to lift the same load to the same height. Compare the effort applied by them. Give a reason to support your answer.
A pulley system with VR = 4 is used to lift a load of 175 kgf through a vertical height of 15 m. The effort required is 50 kgf in the downward direction. (g = 10 N kg-1)
Calculate:
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- Work done by the effort
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- Efficiency of the pulley system
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- mechanical advantage,
- Velocity ratio and
- efficiency of the combination in ideal situation.
Give reason for the following:
In case of a block and tackle arrangement, the mechanical advantage increases with the increase in the number of pulleys.
The mechanical advantage of an ideal single movable pulley is ______.
Give reason for the following:
In case of a block and tackle system, the mechanical advantage increases with the increase in the number of pulleys.
Write two uses of pulleys. Is pulley a force multiplier?
A pulley is a machine made up of a ______.
