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प्रश्न
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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उत्तर
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.
संबंधित प्रश्न
Select the correct alternative:
A pulley is used because of it
What is the mechanical advantage of an ideal pulley?
Answer the following in detail.
How does a pulley make work simpler?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while gaining speed on the road ?
What should be the gear ration of a car : equal to 1, less than 1 or greater than 1, while ascending a hill ?
Give two reasons why the efficiency of a single movable pulley system is not 100%.
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
Give reason for the following:
The efficiency of a pulley is always less than 100%
A type of single pulley is very often used as a machine even though it does not give any gain in mechanical advantage. For what purpose is such a pulley used?
A pulley system has a velocity ratio of 4 and an efficiency of 90%. Calculate:
(i) the mechanical advantage of the system.
(ii) the effort required to raise a load of 300 N by the system.
