a man has only 4 simple pulleys to lift a heavy load of 6000N. in roder to lift the load easily, he combines the pulleys (3 moveable, 1 fixed). given that the frictional forces are 300N, what force must he apply in order to lift the load?
The ideal mechanical advantage is 4, the number of pulleys. The ideal force required to lift 6000N would be 6000/4 = 1500 N.
Add 300 N to that for frictional resistance.
ur wrong
1500N
STUDENT
To solve this problem, we need to understand the concept of mechanical advantage provided by pulleys.
A simple pulley system consists of a rope or cable wrapped around a wheel or axle. In this case, the man has four pulleys, three moveable and one fixed. Each moveable pulley has an individual mechanical advantage of 2 (as it reduces the force needed to lift the load by half), while the fixed pulley does not provide any mechanical advantage.
To calculate the total mechanical advantage of the combined pulleys system, we multiply the mechanical advantages of each moveable pulley together. So, for three moveable pulleys, the total mechanical advantage will be 2 * 2 * 2 = 8.
The frictional forces of 300N do not affect the mechanical advantage of the pulley system. These forces only add to the total force required to lift the load.
Now, to determine the force the man must apply to lift the load, we divide the load's weight by the total mechanical advantage. In this case, the load weighs 6000N, and the total mechanical advantage is 8.
So, the force the man must apply to lift the load is 6000N / 8 = 750N.
However, since there are frictional forces involved, we need to account for them as well. The frictional forces of 300N oppose the motion of the pulley system, and the man needs to overcome this resistance. Therefore, in order to lift the load, the man must apply a force of 750N + 300N = 1050N.
In summary, the man must apply a force of 1050N in order to lift the load of 6000N with the combined pulley system.