A 100% efficient light bulb is the one that converts all the electricity to light without producing any heat. which of that following methods is the most economical way of increasing the light output from a lamp ?
a) Replace the light with a new one
b) Clean the light surface
c) Switch of the bulb
d) None of the above
Answer:
d
Explanation:
Buying a new light bulb will cost money so it is economically inefficient. Cleaning the light surface doesn't increase the light output from the lamp and switching off the bulb means no light at all, therfore the answer is none of the above.