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प्रश्न
Differentiate between a single fixed pulley and a single movable pulley.
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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 |
संबंधित प्रश्न
From the diagram given below. answer the question that follows:
1) What kind of pulleys are A and B?
2) State the purpose of pulley B.
3) What effort has to be applied at C just raise the load L = 20 kgf?
(Neglect the weight of pulley A and friction)
Is the above pulley system an ideal machine or not?
Select the correct alternative:
A pulley is used because of it
State two functions of a machine.
Answer the following in detail.
How does a pulley make work simpler?
In a gear system, the gear ration of the driving wheel A and driven wheel B is 10:1. To rotate the driven wheel B in the direction of driving wheel A, the driving wheel A is engaged with other wheel C. what should be the gear ratio of the wheels A and C?
The diagram below shows an arrangement of three pulleys A, B, and C. The load is marked as L and the effort as E.
- Name the Pulleys A, B, and C.
- Mark in the diagram the directions of load (L), effort (E) and tension T1 and T2 in the two strings.
- How are the magnitudes of L and E related to the tension T1?
- Calculate the mechanical advantage and velocity ratio of the arrangement.
- What assumptions have you made in parts (c) and (d)?
Draw a diagram of a single fixed pulley and obtain expressions for its:
(i) Mechanical advantage,
(ii) Velocity ratio, and
(iii) Efficiency, in the ideal case.
The alongside figure shows the combination of a movable pulley P1 with a fixed pulley P2 used for lifting up a load W.
(i) State the function of the fixed pulley P2.
(ii) If the free end of the string moves through a distance x, find the distance by which the load W is raised.
(iii) Calculate the force to be applied at C to just raise the load W = 20 kgf, neglecting the weight of the pulley P1 and friction.
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.
