FireTEAM Test FireTEAM Mechanical Aptitude 3

Question 1

A firefighter needs to lift a 300-pound engine block using a pulley system with 3 supporting rope segments. How much force must the firefighter apply (ignoring friction)?

Accepted Answer

100 lbs

Answer

With 3 supporting rope segments, mechanical advantage is 3, so required force = 300 ÷ 3 = 100 lbs.

Question 2

A closed hydraulic system has a small piston with a 2 sq-in area and a large piston with a 20 sq-in area. If 50 lbs of force is applied to the small piston, what force is generated at the large piston?

Accepted Answer

500 lbs

Answer

Pascal's law: force at large piston = (large area / small area) × input force = (20/2) × 50 = 500 lbs.

Question 3

Two gears are meshed: Gear A has 12 teeth and Gear B has 48 teeth. If Gear A spins at 200 RPM, how fast does Gear B spin?

Accepted Answer

50 RPM

Answer

Gear ratio = 12/48 = 1/4, so Gear B turns at 200 × (12/48) = 50 RPM.

Question 4

A firefighter rolls a heavy oxygen cylinder up a ramp that is 12 feet long and 3 feet high. What is the ideal mechanical advantage of this inclined plane?

Accepted Answer

4

Answer

Mechanical advantage of an inclined plane = length ÷ height = 12 ÷ 3 = 4.

Question 5

A pressure gauge reads 65 PSI at the base of a standpipe. Accounting for water pressure loss of approximately 0.43 PSI per foot of elevation, what is the approximate pressure at a point 50 feet higher?

Accepted Answer

43.5 PSI

Answer

Pressure drop = 50 × 0.43 = 21.5 PSI, so pressure at the higher point = 65 − 21.5 = 43.5 PSI.

FireTEAM Practice Test

FireTEAM Practice Test

FireTEAM Test FireTEAM Mechanical Aptitude 3