WTMA Aptitude Knowledge 5

Question 1

A conveyor belt moves at 10 ft/min and is driven by a drum 1 foot in diameter. The drum's rotational speed is approximately:

Accepted Answer

3.18 RPM

Answer

Belt speed = RPM × circumference; RPM = 10 ÷ (π × 1) ≈ 10 ÷ 3.14 ≈ 3.18 RPM.

Question 2

Which effect occurs when a fluid moves faster, causing a decrease in pressure?

Accepted Answer

Bernoulli's effect

Answer

Bernoulli's principle states that as fluid velocity increases, pressure decreases, which explains lift in airplane wings and carburetor operation.

Question 3

Two boxes are stacked. Box A (20 lbs) sits on Box B (30 lbs) on the floor. The force the floor exerts on Box B is:

Accepted Answer

50 lb

Answer

The floor supports both boxes together; normal force = 20 + 30 = 50 lb (Newton's third law).

Question 4

A worm gear set has a worm with 1 start and a worm wheel with 40 teeth. The gear ratio is:

Accepted Answer

40:1

Answer

Worm gear ratio = worm wheel teeth ÷ worm starts = 40 ÷ 1 = 40:1, meaning the worm turns 40 times for each rotation of the wheel.

Question 5

A fuse in an electrical circuit is designed to:

Accepted Answer

Break the circuit when current is too high

Answer

A fuse contains a metal element that melts and breaks the circuit when current exceeds a safe level, protecting equipment from damage.

WTMA - Wiesen Test of Mechanical Aptitude Practice Test