CAT Material Selection & Properties 3

Question 1

Which property of a material describes its ability to return to its original shape after being bent or stretched?

Accepted Answer

Elasticity

Answer

Elasticity is the material property that allows it to recover its original dimensions after deformation.

Question 2

A technician is installing a glass-break sensor on a framed picture window. Which glass type will produce the most reliable frequency signature for detection?

Accepted Answer

Annealed (float) glass

Answer

Annealed (float) glass shatters into large shards producing the classic high-frequency flex-and-break signature that glass-break sensors are tuned to detect.

Question 3

What does the 'mil' unit measure when specifying wire insulation thickness?

Accepted Answer

Thousandths of an inch

Answer

One mil equals one thousandth of an inch (0.001"), a standard unit for measuring insulation and jacket thickness.

Question 4

When splicing alarm wiring in an outdoor junction box, which material should be used to protect splice connections from moisture?

Accepted Answer

Silicone-filled (waterproof) wire nuts or gel-filled connectors

Answer

Silicone or gel-filled connectors seal out moisture at the conductor interface, preventing corrosion and resistance changes outdoors.

Question 5

A UL-listed alarm system requires end-of-line resistors. Which resistor body material provides the best long-term stability against temperature-induced value drift?

Accepted Answer

Metal film

Answer

Metal film resistors have low temperature coefficients and excellent stability over time compared to carbon composition or carbon film types.

(CAT) Certified Alarm Technician Level I Practice Test

(CAT) Certified Alarm Technician Level I Practice Test

CAT Material Selection & Properties 3