Ramsay Test Mechanical Aptitude 5

Question 1

A compound gear train has a 12-tooth driver gear meshing with a 48-tooth intermediate gear. The intermediate gear is on the same shaft as an 8-tooth pinion, which drives a 40-tooth output gear. What is the overall gear ratio (input to output)?

Accepted Answer

20:1

Answer

In a compound gear train, multiply the individual ratios. Stage 1: 48/12 = 4:1. Stage 2: 40/8 = 5:1. Overall ratio = 4 × 5 = 20:1. This means the output shaft rotates once for every 20 rotations of the input shaft.

Question 2

A hydraulic jack uses a small piston with a 1-inch diameter and a large piston with a 4-inch diameter. If you apply 50 lbs of force to the small piston, what load can the large piston lift?

Accepted Answer

800 lbs

Answer

Pascal's Law states pressure is equal throughout. Pressure = Force / Area. Small piston area = π(0.5)² ≈ 0.785 in². Large piston area = π(2)² ≈ 12.57 in². Ratio of areas = 12.57 / 0.785 = 16. Output force = 50 × 16 = 800 lbs. The diameter ratio is 4:1 but the area ratio is 16:1 because area scales with the square of diameter.

Question 3

Two identical springs are connected in parallel (side by side, both attached to the same load). Each spring has a spring constant of 120 N/m. What is the effective spring constant of the parallel combination?

Accepted Answer

240 N/m

Answer

Springs in parallel add their constants directly: k_total = k1 + k2 = 120 + 120 = 240 N/m. This is the opposite of series, where constants combine as reciprocals. In parallel, both springs share the load and both compress equally, so the system is stiffer than either spring alone.

Question 4

A 10-foot lever is used to move a heavy rock. The fulcrum is placed 2 feet from the rock (load end). A worker applies force at the opposite end. Compared to the load, the force required is approximately:

Accepted Answer

1/4 of the load

Answer

The effort arm = 10 - 2 = 8 feet. The load arm = 2 feet. Mechanical advantage = effort arm / load arm = 8/2 = 4. Therefore, force required = load / 4, or 1/4 of the load. The worker benefits from a 4:1 mechanical advantage by placing the fulcrum close to the load.

Question 5

A pulley system has two fixed pulleys and two movable pulleys arranged as a block and tackle. The rope is pulled 12 feet to raise a load. How far does the load rise?

Accepted Answer

3 feet

Answer

A block and tackle with 2 fixed and 2 movable pulleys has 4 rope segments supporting the movable block, giving a mechanical advantage of 4. The load rises 1/4 as far as the rope is pulled: 12 ÷ 4 = 3 feet. The trade-off is that you pull 4 feet of rope for every 1 foot the load rises.

Ramsay Test Practice Test

Ramsay Test Practice Test

Ramsay Test Mechanical Aptitude 5