FCTC Test Pulleys, Gears, and Levers 1

Question 1

A movable pulley is used to lift a 240-lb load. Ignoring friction, how much force must be applied to the rope?

Accepted Answer

120 lb

Answer

A movable pulley provides a mechanical advantage of 2 because two rope segments support the load. The required effort is 240 ÷ 2 = 120 lb.

Question 2

Gear X has 20 teeth and Gear Y has 80 teeth. If Gear X rotates at 160 RPM, how fast does Gear Y rotate?

Accepted Answer

40 RPM

Answer

The speed ratio is inversely proportional to the number of teeth: (20 ÷ 80) × 160 = 40 RPM. The larger gear always turns more slowly than the smaller driver gear.

Question 3

A lever has an effort arm of 6 feet and a resistance arm of 2 feet. What is the mechanical advantage?

Accepted Answer

3

Answer

Mechanical advantage of a lever = effort arm ÷ resistance arm = 6 ÷ 2 = 3. This means a 3:1 force multiplication is achieved.

Question 4

A block-and-tackle system applies 50 lbs of effort through 6 rope segments supporting the load. What is the maximum load that can be lifted, ignoring friction?

Accepted Answer

300 lb

Answer

The mechanical advantage equals the number of supporting rope segments (6), so the maximum load = 6 × 50 = 300 lb.

Question 5

Which of the following is an example of a third-class lever?

Accepted Answer

Fishing rod

Answer

A fishing rod is a third-class lever: the effort (hand gripping the rod) is applied between the fulcrum (the butt end) and the load (the fish). Third-class levers trade force for speed and range of motion.

FCTC Test Practice Test

FCTC Test Practice Test

FCTC Test Pulleys, Gears, and Levers 1