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प्रश्न
In a single movable pulley system, a load of 125 kgf is lifted by an effort of 75 kgf. Find the percentage efficiency of system.
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उत्तर
V.R. of single movable pulley = No. of supporting segments of string = 2
M.A. of single movable pulley =`"L"/"E"=125/75=5/3`
% efficiency =`"M.A."/"V.R."xx100`
= `(5xx100)/(3xx2)=83%.`
संबंधित प्रश्न
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)
State whether the following statement is True or False.
A pulley changes the direction of force.
What is a pulley?
What is the justification for using the pulley then ?
State if the following statement is true or false. Correct the statement if it is false.
A single movable pulley is a pulley that has its axis of rotation fixed.
Name a machine to change the direction of force ?
Explain how a gear system can be used to obtain Change in direction of rotation. Given one example.
Give a reason for the following:
In a single fixed pulley, the velocity ratio is always more than the mechanical advantage.
In the alongside the figure of two pulleys shown a system in which one pulley is fixed and the other is movable. What is the velocity ratio of the system?
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?
The alongside figure shows the combination of a movable pulley P1 with a fixed pulley P2 used for lifting up a load W.
(i) State the function of the fixed pulley P2.
(ii) If the free end of the string moves through a distance x, find the distance by which the load W is raised.
(iii) Calculate the force to be applied at C to just raise the load W = 20 kgf, neglecting the weight of the pulley P1 and friction.
