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प्रश्न
Differentiate between a single fixed pulley and a single movable pulley.
उत्तर
| Single fixed pulley | Single movable pulley |
| 1. It is fixed to a rigid support. | 1. It is not fixed to a rigid support |
| 2. Its mechanical advantage is one . | 2. Its mechanical advantage is two. |
| 3. Its velocity ratio is one. | 3. Its velocity ratio is two. |
| 4. The weight of pulley itself does not affect its mechanical advantage. | 4. The weight of pulley itself reduces its mechanical advantage. |
| 5. It is used to change the direction of effort | 5. It is used as force multiplie |
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संबंधित प्रश्न
Select the correct alternative:
A pulley is used because of it
Name the type of single pulley that can act as a force multiplier. Draw a labelled diagram of the pulley mentioned by you.
Draw a diagram of a combination of three movable pulleys and one fixed pulley to lift up a load. In the diagram, show the directions of load, effort and tension in each strand. Find:
- mechanical advantage,
- Velocity ratio and
- efficiency of the combination in ideal situation.
Give reason for the following:
In case of a block and tackle arrangement, the mechanical advantage increases with the increase in the number of pulleys.
What is the use of a fixed pulley?
Write two uses of pulleys. Is pulley a force multiplier?
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?
If the weight of the movable pulley is W, obtain the expression for MA, VR, and efficiency.
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.
State one advantage of single movable pulley.
