EIAT Mechanical Aptitude 3

Question 1

A wire rope used in elevator hoisting is inspected and found to have broken wires. According to general safety standards, a rope should be replaced if it has how many broken wires in one lay length?

Accepted Answer

6 or more

Answer

Industry standards typically require replacement of hoist ropes when 6 or more broken wires are found in one rope lay length.

Question 2

In a block and tackle system using 4 rope segments supporting the load, a 400 lb load requires approximately how much pulling force (ignoring friction)?

Accepted Answer

100 lb

Answer

With 4 supporting rope segments, the mechanical advantage is 4, so the effort force is 400 ÷ 4 = 100 lb.

Question 3

What is the function of a worm gear drive in elevator machinery?

Accepted Answer

Provide high speed reduction and self-locking capability

Answer

Worm gear drives achieve large speed reductions in a compact package and are often self-locking, preventing back-driving under load.

Question 4

If a spring is compressed by 3 inches with a force of 90 lb, what force is needed to compress it an additional 1 inch (to 4 inches total), assuming it follows Hooke's Law?

Accepted Answer

120 lb

Answer

The spring constant is 90 ÷ 3 = 30 lb/in, so 4 inches of compression requires 30 × 4 = 120 lb.

Question 5

A sheave (pulley wheel) in an elevator system with a worn groove will most likely cause:

Accepted Answer

Increased rope wear and possible slippage

Answer

Worn or mismatched grooves reduce the contact area between rope and sheave, accelerating rope wear and reducing traction.

EIAT - Elevator Industry Aptitude Test Practice Test

EIAT - Elevator Industry Aptitude Test Practice Test

EIAT Mechanical Aptitude 3