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प्रश्न
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उत्तर
In a single fixed pulley, if the effort moves by a distance 'y' downwards, the load moves by a distance 'y' upwards because the velocity ratio of a single fixed pulley is 1.
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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)
A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50N. Calculate the Mechanical Advantage and Efficiency of this system.
State whether the following statement is True or False.
A pulley changes the direction of force.
Draw a neat labelled diagram showing a pulley being used to lift a load. How are load and effort related in an ideal situation?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while ascending a hill ?
The diagram below shows a pulley arrangement.

(i) In the diagram, mark the direction of the forces due to tension, acting on the pulley P.
(ii) What is the purpose of the pulley Q?
(iii) If the tension is T newton, deduce the relation between T and E.
(iv) Calculate the velocity ratio of the arrangement.
(v) Assuming that the efficiency of the system is 100%, what is the mechanical advantage?
(vi) Calculate the value of E
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
What is a block and tackle system of pulleys? What precautions would you observe while rounding the string so that the effort is applied in the downward direction?
Diagram given below shows an arrangement of four pulleys. A load L is attached to the movable lower block and effort E is applied at the free end of the string.
Copy the diagram; and

(i) Draw arrows to indicate tension in each part of the string; and
(ii) Calculate the mechanical advantage of the system.
A man raises a load of 360 kgf using a block and tackle system of 3 pulleys. If the efficiency of the pulley system is 60%, what effort is applied by the man?
