What is the velocity ratio of a single movable pulley? How does the friction in the pulley bearing affect it?

What is the velocity ratio of a single movable pulley? How does the friction in the pulley bearing affect it?

Class 10 | ICSE | Machines | Physics | Selina

What is the velocity ratio of a single movable pulley? How does the friction in the pulley bearing affect it?

Solutions:

The velocity ratio of a single movable pulley is always 2. The friction in the pulley bearing has no effect.

When a load is lifted down by a certain distance, the force must be applied twice as far because when any object attached to a pulley is lifted, force is applied to the ropes on opposite sides of the pulley because one side rope moves upward while the other side rope moves downward by the same distance. So, the formula for velocity ratio in such a case becomes –

Velocity ratio = (distance travelled by effort) / (distance travelled by load)

VR = 2X/X = 2

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