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Question
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)?
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Solution
(a) Pulleys A and B are movable pulleys. Pulley C is a fixed pulley.
(b)
(c) L = 4T1; E = T1
(d) M.A. = `L/E`
M.A. = `(4T_1)/T_1`
M.A. = 4
V.R. = `(4d)/d = 4`
(e)
- There is less weight on pulleys A and B.
- There's no friction at all between the axle and the pulleys.
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RELATED QUESTIONS
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_______ is a machine made up of wheel and rope.
Complete the table.
| S. No | Types of Simple Machine | Example |
| 1. | Pulley | |
| 2. | Wheel and axle | |
| 3. | Wedge | |
| 4. | Inclined plan | |
| 5. | Lever | |
| 6. | Screw |
