Test Pulleys, Gears, and Levers Questions and Answers Flashcards

A movable pulley is attached to a 200 lb load, and a fixed pulley redirects the rope. How much effort is required to lift the load (ignore friction)?

Answer: 100 lbs

A movable pulley provides a mechanical advantage of 2, so the required effort is 200 ÷ 2 = 100 lbs.

A large driving gear has 48 teeth and turns a small gear with 12 teeth. How would you describe the output of the small gear compared to the input?

Answer: Higher speed, less torque

When a large gear drives a smaller gear, the smaller gear spins faster but produces less torque.

A lever's mechanical advantage is calculated as:

Answer: Effort arm length ÷ Load arm length

Mechanical advantage of a lever = Effort arm length ÷ Load arm length, indicating how much force is multiplied.

In a block-and-tackle system with 3 movable pulleys and 3 fixed pulleys, what is the maximum mechanical advantage possible?

Answer: 6

With 3 movable pulleys the mechanical advantage equals the number of rope segments supporting the load, which is 6.

Three gears are arranged in a line: A drives B, and B drives C. Gears A and C will rotate in which direction relative to each other?

Answer: The same direction

With three gears in a series (A→B→C), an odd number of gear meshes means the first and last gear rotate in the same direction.

A crowbar (first-class lever) is used to pry open a crate. The fulcrum is placed 4 inches from the load and the firefighter pushes down 32 inches from the fulcrum. What is the mechanical advantage?

Answer: 8

MA = Effort arm ÷ Load arm = 32 ÷ 4 = 8, meaning the firefighter multiplies their force by 8.

When using a pulley system, if the effort rope is pulled 6 feet to raise a load, but the load only rises 1 foot, what is the mechanical advantage?

Answer: 6

Mechanical advantage = distance effort moves ÷ distance load moves = 6 ÷ 1 = 6.