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प्रश्न
Name the type of single pulley that can act as a force multiplier. Draw a labeled diagram of the pulley mentioned by you.
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उत्तर
single movable pulley acts as a force multiplier.
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संबंधित प्रश्न
From the diagram given below. answer the question that follows:
- What kind of pulleys are A and B?
- State the purpose of pulley B.
- What effort has to be applied at C just raise the load L = 20 kgf?
(Neglect the weight of pulley A and friction)
Fill in the blank:
A pulley is used to change ........................
What is a pulley?
The mechanical advantage of an actual pulley is less than one. Give a reason. What is the justification for using the pulley then?
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.
In the alongside the figure of two pulleys shown a system in which one pulley is fixed and the other is movable. What is the velocity ratio of the system?
An effort of 600 N is needed to lift a weight of 1000 N. What are the mechanical advantage and efficiency of the pulley system?
A block and tackle system of pulleys has a velocity ratio of 4.
- Draw a labelled diagram of the system indicating clearly the points of application and directions of load and effort.
- What is the value of the mechanical advantage of the given pulley system if it is an ideal pulley system?
A boy lifts a load of 40 kgf through a vertical height of 2m in 5s by using a single fixed pulley when he applies an effort of 48 kgf. Calculate:
(i) the mechanical advantage, and
(ii) the efficiency of the pulley. Why is the efficiency of the pulley is not 100%?
(iii) the energy gained by the load in 5s, and
(iv) the power developed by the boy in raising the load.
| 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?
