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Question
Give reason for the following:
In a single fixed pulley, the velocity ratio is always more than the mechanical advantage.
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Solution
In a single fixed pulley, some effort is wasted in overcoming friction between the strings and the grooves of the pulley; so the effort needed is greater than the load and hence the mechanical advantage is less than the velocity ratio.
RELATED QUESTIONS
What is the mechanical advantage of an ideal pulley?
Answer the following in detail.
How does a pulley make work simpler?
The diagram below shows a pulley arrangement.
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Fig shown a block and tackles system of pulleys used to lift a load.
(i) How many strands of tackle are supporting the load?
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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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An effort of 600 N is needed to lift a weight of 1000 N. What are the mechanical advantage and efficiency of the pulley system?
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.
