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प्रश्न
Name the type of single pulley that can act as a force multiplier. Draw a labelled diagram of the pulley mentioned by you.
उत्तर
A single movable pulley act as a force multiplier.
Diagram:
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संबंधित प्रश्न
A pulley system has three pulleys. A load of 120 N is overcome by applying an effort of 50N. Calculate the Mechanical Advantage and Efficiency of this system.
Is the above pulley system an ideal machine or not?
What is the mechanical advantage of an ideal pulley?
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?
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.
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.
Diagram given below shows an arrangement of four pulleys. A load L is attached to the movable lower block and effort E is applied at the free end of the string.
Copy the diagram; and
(i) Draw arrows to indicate tension in each part of the string; and
(ii) Calculate the mechanical advantage of the system.
In a single movable pulley system, a load of 125 kgf is lifted by an effort of 75 kgf. Find the percentage efficiency of system.
