5A
YOUR ANSWER: Both the above.
Very good.
Electrical power is the time rate at which charge is forced to move by voltage. This is
why the power in watts is equal to the product of volts and amperes. Thus, the basic power
formula is P = E x I.
For example, when a 6-volt battery produces 2 amps, in a circuit, the battery is
producing 12 watts of power.
The voltage states the amount of work per unit of charge, and the current includes the
time rate at which the charge is moved.
There is a further example of the relationship between electrical power and mechanical
power in the fact that
746 watts = 1 horsepower = 550 ft.-lbs. per second.
746 watts = 1 horsepower = 33,000 ft.-lbs. per minute.
The unit of measurement for the amount of power consumed in a circuit is the
watt. frame 2A
volt.
frame 8A
5B
YOUR ANSWER: Power = work x time.
Come, come now.
Power is the time rate for doing work or consuming energy.
When we talk about the rate of something, we are going to divide that "something" by
time. For example: If you drove 200 miles in 5 hours, you would have to divide 200 by 5 to
find out how many miles-per-hour you were traveling. there are many other such "rates," such
as miles-per-gallon, gallons-per-minute, or, in our case, salary-per-month. These are all
"rates," some quantity per unit of time.
Return now to frame 1A and select the correct answer.
IT0348
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