- #1
Gyro
- 49
- 0
Let's say I have a 2-pulley system, with the effort force F being pulled upwards. The load is attached to the lower movable pully P1 where the rope is fixed. The rope extends up to the fixed pulley on the ceiling P2, wraps around, then travels back down to the side of the lower pulley, wraps around, and meets the effort force. As shown below:
---------
____|_______F
____|______/
___/P2\ ___/
___|__|___/
___|__/__/
___|_/__/
___|_/_/
___|P1/
____|
____|
L
I'm told the TMA is 3 since there are 3 supporting strands of rope. So since W = Fd is constant, does that mean for every unit of distance I pull at F, the load will rise 1/3 units? If so, how, since there are only 2 other supporting segments of the rope? I mean, how do 2 supporting strands move to make up the 1 unit pulled at F? Wouldn't having 2 supporting strands imply the load is raised 1/2 unit? But if W is constant, ...?
I'm stumped.
---------
____|_______F
____|______/
___/P2\ ___/
___|__|___/
___|__/__/
___|_/__/
___|_/_/
___|P1/
____|
____|
L
I'm told the TMA is 3 since there are 3 supporting strands of rope. So since W = Fd is constant, does that mean for every unit of distance I pull at F, the load will rise 1/3 units? If so, how, since there are only 2 other supporting segments of the rope? I mean, how do 2 supporting strands move to make up the 1 unit pulled at F? Wouldn't having 2 supporting strands imply the load is raised 1/2 unit? But if W is constant, ...?
I'm stumped.