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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
The pulley system has drawn lifts a load of 150 N when an effort of 60 N is applied. Find its mechanical advantage.
State whether the following statement is True or False.
A pulley changes the direction of force.
What is a pulley?
Answer the following in short.
Explain the various functions that a machine can perform.
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.
What is a block and tackle system of pulleys?
Draw the diagram of a single movable pulley and obtain its mechanical advantage, velocity ratio, and efficiency.
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?
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?
