CPS Mechanical Aptitude Principles 4

Question 1

On a balanced seesaw, a 60-lb child sits 4 ft from the pivot. How far from the pivot must a 40-lb child sit to balance it?

Accepted Answer

6 ft

Answer

60 × 4 = 240, so 40 × d = 240 gives d = 6 ft.

Question 2

A screw is best described as which simple machine wrapped around a cylinder?

Accepted Answer

An inclined plane

Answer

A screw is an inclined plane wound spirally around a central shaft.

Question 3

When two pulleys are connected by a belt and one is larger, the larger pulley does what compared to the smaller?

Accepted Answer

Turns slower

Answer

A larger driven pulley rotates more slowly than a smaller one connected by the same belt.

Question 4

A spring is compressed and held in place. What type of energy does it store?

Accepted Answer

Potential energy

Answer

A compressed spring stores potential energy, released as motion when freed.

Question 5

In a system of meshed gears, a small gear drives a large gear. What happens to the torque output?

Accepted Answer

Torque increases

Answer

Driving a larger gear increases torque while reducing rotational speed.

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