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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
From the diagram given below. answer the question that follows:
1) What kind of pulleys are A and B?
2) State the purpose of pulley B.
3) What effort has to be applied at C just raise the load L = 20 kgf?
(Neglect the weight of pulley A and friction)
Fill in the blank:
A pulley is used to change ........................
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Answer the following in short.
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(i) Copy the diagram and mark the direction of tension on each strand of the string.
(ii) What is the velocity ratio of the arrangement ?
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(iv) If the free end of the string moves through distance x, find the distance by which the load is raised.
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- Draw a labelled diagram of the system indicating clearly the points of application and directions of load and effort.
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| Meera chose to use a block and tackle system of '9' pulleys instead of a single movable pulley to lift a heavy load. |
Why should she connect more number of pulleys in the upper fixed block?
Name the type of single pulley that has an ideal mechanical advantage equal to 2. Draw a labelled diagram of the pulley mentioned by you.
