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Questions
Differentiate between a single fixed pulley and a single movable pulley.
State four differences between a single fixed pulley and a single movable pulley.
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Solution
| Single fixed pulley | Single movable pulley | |
| 1. | This pulley has a fixed axis of rotation. | The axis of rotation of this pulley is not fixed. |
| 2. | The load is attached to one end of the rope. | The load is attached to the pulley. |
| 3. | Only the direction of the force is changed, not the magnitude. [We can lift the object higher, but the heaviness of load remains the same.] | The direction of the force as well as the magnitude of the force change. |
| 4. | The mechanical advantage of this pulley is 1. | The mechanical advantage of this pulley is 2. |
| 5. | Example: Used to draw water from wells. | Example: Used in construction cranes, Weight lifting, machines in the gym, etc. |
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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 |
