WTMA Mechanical Comprehension 5

Question 1

A centrifugal pump spins faster. What happens to the water pressure it produces?

Accepted Answer

Pressure increases

Answer

Centrifugal pumps use rotational speed to impart kinetic energy to fluid; higher speed increases the centrifugal force and therefore the output pressure.

Question 2

A conveyor belt is driven by a large pulley (diameter 20 in) connected by a belt to a small pulley (diameter 5 in) on a motor. If the motor spins at 400 RPM, how fast does the large pulley turn?

Accepted Answer

100 RPM

Answer

Speed ratio inversely follows the diameter ratio: large pulley speed = 400 × (5/20) = 100 RPM.

Question 3

Which statement best describes the purpose of a torque wrench?

Accepted Answer

It applies a precisely measured rotational force to a fastener

Answer

A torque wrench measures and limits the rotational force applied to a fastener, preventing over-tightening that can strip threads or break bolts.

Question 4

Two objects with different masses are dropped from the same height in a vacuum. Which hits the ground first?

Accepted Answer

They hit at the same time

Answer

In a vacuum, gravity accelerates all objects equally regardless of mass (9.8 m/s²), so both objects fall at identical rates and land simultaneously.

Question 5

A screwdriver is turned 10 full rotations to drive a screw 0.5 inches into wood. What is the thread pitch of the screw?

Accepted Answer

0.05 inches per turn

Answer

Thread pitch = total distance ÷ number of turns = 0.5 ÷ 10 = 0.05 inches per turn.

WTMA - Wiesen Test of Mechanical Aptitude Practice Test

WTMA - Wiesen Test of Mechanical Aptitude Practice Test

WTMA Mechanical Comprehension 5