FCTC Test Pulleys, Gears, and Levers Questions and Answers 3

Question 1

A pulley system uses one fixed pulley and one movable pulley. How many rope segments support the movable block?

Accepted Answer

2

Answer

A single movable pulley has 2 rope segments supporting the load block, giving a mechanical advantage of 2.

Question 2

Gear A has 20 teeth and drives Gear B with 20 teeth, which in turn drives Gear C with 40 teeth. What is the overall speed ratio from Gear A to Gear C?

Accepted Answer

1:2

Answer

Stage 1 (A to B): 20 divided by 20 equals 1:1 (same speed). Stage 2 (B to C): 20 divided by 40 means C runs at half of B speed. Overall: Gear C turns at half the speed of Gear A, giving a 1:2 ratio.

Question 3

A Class 3 lever always has the effort applied between the fulcrum and the load. What is always true of a Class 3 lever?

Accepted Answer

MA is always less than 1, requiring more effort force than the load

Answer

Class 3 levers always have the effort arm shorter than the load arm, so MA is always less than 1 and more effort is required than the load weight.

Question 4

A worm gear system has a worm with 1 thread and a worm wheel with 40 teeth. The worm turns at 400 RPM. At what RPM does the worm wheel turn?

Accepted Answer

10 RPM

Answer

Worm gear ratio equals worm wheel teeth divided by worm threads: 40 divided by 1 equals 40:1. Worm wheel RPM equals 400 divided by 40 equals 10 RPM.

Question 5

A firefighter applies 80 lbs of force to a lever handle. The fulcrum is 6 inches from the load end and the handle is 24 inches long total. What is the mechanical advantage?

Accepted Answer

3

Answer

Effort arm equals 24 minus 6 equals 18 inches; load arm equals 6 inches; MA equals 18 divided by 6 equals 3.

FCTC Test Practice Test

FCTC Test Practice Test

FCTC Test Pulleys, Gears, and Levers Questions and Answers 3