EIAT Gears, Pulleys, and Levers 4

Question 1

In a block and tackle system with 3 movable pulleys, how many rope segments support the load?

Accepted Answer

6

Answer

Each movable pulley adds 2 rope segments, so 3 movable pulleys provide 6 supporting rope segments and a MA of 6.

Question 2

A pinion gear with 15 teeth drives a ring gear with 75 teeth. If the pinion turns at 500 RPM, the ring gear turns at:

Accepted Answer

100 RPM

Answer

Output RPM = Input RPM × (driver teeth ÷ driven teeth) = 500 × (15 ÷ 75) = 100 RPM.

Question 3

What is the purpose of a counterweight in an elevator system?

Accepted Answer

To reduce the motor load by balancing the car weight

Answer

A counterweight approximately equals the car weight plus half the rated load, reducing the net force the motor must overcome.

Question 4

When a small gear drives a large gear, the output shaft produces:

Accepted Answer

Lower speed and higher torque

Answer

Driving a larger gear results in a speed decrease and a proportional torque increase at the output shaft.

Question 5

A rack and pinion gear system converts:

Accepted Answer

Rotary motion to linear motion

Answer

A rack and pinion converts the rotational motion of the pinion into the linear (straight-line) motion of the rack.

EIAT - Elevator Industry Aptitude Test Practice Test