ganesh wanted to lift a heavy basket of books to the tree house. he found it difficult to to lift the books using the single fixed pulley. Why is that so?
2007-08-24 15:09:38 · 5 answers · asked by Anonymous in Science & Mathematics ➔ Physics
The books were too heavy... he should use multiple pulleys to reduce the effective weight being lifted.
2007-08-24 15:17:53 · answer #1 · answered by prbfc 5 · 1⤊ 0⤋
Single pulley requires that the lifting force be greater than the weight of the load being lifted.
You can get what is called "mechanical advantage" by going to multiple pulleys, so that the total force which you must apply can be less than the weight of what you are trying to lift. However, it does not come for free. If you must lift a 100 lb bag 10 feet, and you use a (frictionless) pulley system to get the lift load down to 10 lbs, you must "lift" the rope for 100 feet (need a long rope.
Single pulley requires maximum force for the minimum distance. Multiple pulleys reduce the required force, but will increase the distance which the system must be "pulled through"
2007-08-24 22:25:07 · answer #2 · answered by Bernie 2 · 1⤊ 0⤋
He misused it. He should have attached the axle of the pulley to the basket, one end of the rope to the tree house, and, standing in the tree house, pulled upward with a force = ½*(weight of books + basket + pulley)
2007-08-24 22:24:08 · answer #3 · answered by Steve 7 · 2⤊ 0⤋
A single pulley just Ganges the direction of your pull.
2007-08-24 22:28:51 · answer #4 · answered by Lindsay 3 · 0⤊ 0⤋
A single pulley just Ganges the direction of your pull. It does not give you a mechanical advantage.
2007-08-24 22:24:53 · answer #5 · answered by Kevin H 7 · 1⤊ 0⤋