- #1
Gear300
- 1,213
- 9
For a pulley, when is it that the mechanical advantage is greater than 1 and when is it that it is equal to 1? If a rope was hung over a pulley with unequal weights applied to both ends, the larger weight (77kg) would pull the lesser weight (30kg) upward, and so what would the mechanical advantage there be?
The thing about this question is that if a rope were hung over a pulley and the tension at each point was the same (neglecting the mass of the rope and pulley), then how is it that if both ends of the rope point downward that the mechanical advantage becomes 2 (if there was just that one pulley)? Is the mechanical advantage any different if someone was applying a force to one end of the rope compared to gravity acting alone?
The thing about this question is that if a rope were hung over a pulley and the tension at each point was the same (neglecting the mass of the rope and pulley), then how is it that if both ends of the rope point downward that the mechanical advantage becomes 2 (if there was just that one pulley)? Is the mechanical advantage any different if someone was applying a force to one end of the rope compared to gravity acting alone?