Question: Which of the following are appropriate units for power?
A) newton·meter
B) watt
C) H.P./sec
D) joule/sec
Answer:
Watt and Joule/sec are the appropriate units for power.
Explanation:
As per the question, the physical quantity given is power.
The power is defined as the rate of consumption of energy or the rate of doing work.
Let us consider W is the amount of work done by a body in time t .
Mathematically the power of that body is written as -
power
The unit of work is joule and the unit of time is second.
Hence, the unit of power is joule/sec.
we know that one joule/sec. = one watt.
Hence, watt is also another unit of power. Newton-metre can not be a unit of power . It may be considered as a unit of work.
Similarly H.P/sec is also not a unit of power. Here H.P stands for horse power which is another unit of power . Hence, joule/sec. and watt are the appropriate units of power.