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प्रश्न
Fill in the blank:
A pulley is used to change ........................
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उत्तर
A pulley is used to change the direction of effort.
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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)
What is the mechanical advantage of an ideal pulley?
Explain how a gear system can be used to obtain gain in speed? Given one example.
Define the following term in reference to a gear system of Driving gear ?
The diagram below shows a pulley arrangement :
(i) Copy the diagram and mark the direction of tension on each strand of the string.
(ii) What is the velocity ratio of the arrangement ?
(iii) If the tension acting on the string is T, then what is the relationship between T and effort E ?
(iv) If the free end of the string moves through distance x, find the distance by which the load is raised.
There is no gain in mechanical advantage in the case of a single fixed pulley. Explain, why the pulley is then used?
Draw a diagram of a single fixed pulley and obtain expressions for its:
(i) Mechanical advantage,
(ii) Velocity ratio, and
(iii) Efficiency, in the ideal case.
A ‘block and tackle’ system used 3 pulleys in the lower block and 4 pulleys in the upper block. What is the ‘velocity ratio’ of this system? If the load is to be lifted by a person capable of applying a maximum effort of 1000 N, what is the maximum load than can be lifted under ideal conditions?
The actual maximum load that gets lifted turns out to be 6300 N. What are the values of the actual M.A. and efficiency of the set-up?
| Meera chose to use a block and tackle system of '9' pulleys instead of a single movable pulley to lift a heavy load. |
Why should she connect more number of pulleys in the upper fixed block?
