WTMA Aptitude Knowledge 5 โ Questions and Answers
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:
- 3.18 RPM (Correct answer)
- 10 RPM
- 31.4 RPM
- 6.28 RPM
Correct answer: 3.18 RPM
Belt speed = RPM ร circumference; RPM = 10 รท (ฯ ร 1) โ 10 รท 3.14 โ 3.18 RPM.
Question 2: Which effect occurs when a fluid moves faster, causing a decrease in pressure?
- Pascal's effect
- Archimedes' effect
- Bernoulli's effect (Correct answer)
- Boyle's effect
Correct answer: Bernoulli's effect
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:
- 20 lb
- 30 lb
- 50 lb (Correct answer)
- 10 lb
Correct answer: 50 lb
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:
- 1:1
- 40:1 (Correct answer)
- 1:40
- 20:1
Correct answer: 40:1
Worm gear ratio = worm wheel teeth รท worm starts = 40 รท 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:
- Increase voltage
- Reduce resistance
- Break the circuit when current is too high (Correct answer)
- Store electrical energy
Correct answer: Break the circuit when current is too high
A fuse contains a metal element that melts and breaks the circuit when current exceeds a safe level, protecting equipment from damage.
Question 6: Which type of wrench is best suited for turning nuts in tight spaces where a full rotation is impossible?
- Open-end wrench
- Box-end wrench
- Ratchet wrench (Correct answer)
- Pipe wrench
Correct answer: Ratchet wrench
A ratchet wrench allows back-and-forth motion to tighten fasteners in confined spaces without needing a full 360-degree swing.
Question 7: A flywheel is used in an engine primarily to:
- Increase fuel efficiency
- Store rotational energy and smooth power delivery (Correct answer)
- Cool the engine
- Filter engine oil
Correct answer: Store rotational energy and smooth power delivery
A flywheel stores kinetic energy during power strokes and releases it between strokes, smoothing the engine's rotational output.
WTMA Aptitude Knowledge 5
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: