What are the units of "efficacy"?
A) Foot-candles per inch.
B) Lumens per hour.
C) Candlepower per steradian.
D) Lumens per watt.
D) Lumens per watt.
You might also like to view...
How many times does a 4-stroke cycle diesel engine have to be rotated to ensure that a power stroke takes place in every cylinder?
A. 1/2 rotation B. One rotation C. Two rotations D. Four rotations
When two or more wired partitions are electrically connected together, the cord must be terminated at an attachment plug-and-cord connector equipped with a _____.
a. strain relief device b. stress relief device c. site-isolating device d. positive locking device
According to the electron theory of magnetism, electrons produce a magnetic field as they spin.
Answer the following statement true (T) or false (F)
Why do closed hydronic systems include pressure-relief valves, expansion tanks, and temperature and pressure-limiting devices?
A) Because the copper piping used in the system requires these measures B) Because freezing must be prevented and antifreeze may not be added C) Because building codes require certain controls on every system D) Because water expands and contracts as its temperature changes