Physics
A pulley system has a velocity ratio 3. Draw a diagram showing the point of application and direction of load (L), effort (E) and tension (T).
It lifts a load of 150 N by an effort of 60 N.
Calculate its mechanical advantage.
Is the pulley system ideal? Give reason.
Machines
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Answer
Given,
Effort = 60 N
Load = 150 N
As we know,
Substituting the values in the formula for M.A. we get,
Therefore, Mechanical advantage = 2.5
For an ideal case the M.A. should be equal n, where n is the number of pulleys of the pulley system.
In this case as the mechanical advantage is less than 3 ( i.e. the number of pulleys ) so the pulley system is not ideal.
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