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प्रश्न
In which direction does the force need to applied, when a single pulley is used with a mechanical advantage greater than one? How can you change the direction of force applied without altering its mechanical advantage? Draw a labelled diagram of the system.
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उत्तर
A single movable pulley can be used to obtain an M.A. greater than 1, but this is impractical as it requires exerting force in an upward direction. Instead, a fixed pulley is used in conjunction with the movable pulley to apply force in a downward direction.
The only purpose of a fixed single pulley is to shift the force's application direction in a direction that is convenient.
M.A. = `(2T)/T = 2`
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संबंधित प्रश्न
Fill in the blank:
A pulley is used to change ........................
State if the following statement is true or false. Correct the statement if it is false.
A single movable pulley is a pulley that has its axis of rotation fixed.
Explain how a gear system can be used to obtain gain in speed? Given one example.
Explain how a gear system can be used to obtain gain in torque? Given one example.
Define the following term in reference to a gear system for Gear ratio ?
Give two reasons why the efficiency of a single movable pulley system is not 100%.
The diagram below shows a pulley arrangement.
- Name the pulleys A and B.
- In the diagram, mark the direction of tension on each strand of string.
- What is the purpose of the pulley B?
- If the tension is T, deduce the relation between
- T and E, and
- E and L.
- What is the velocity ratio of the arrangement?
- Assuming that the efficiency of the system is 100%, what is the mechanical advantage?
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?
Draw the diagram of a single movable pulley and obtain its mechanical advantage, velocity ratio, and efficiency.
The pulley system shown in the figure is to be used to lift a load W. If the man applying the effort cannot apply a force exceeding 1000 N, what is the maximum load that can be lifted?
The actual load that the man is finally able to lift turns out to be 2700 N. What are the values of the actual M.A., obtained, and the efficiency of the actual set-up?
