How to solve Watt’s Law Problems

Always write the Watt’s Law circle on a piece of paper

1.   Write the 3 symbols used in Watt’s Law

2.   Enter the information given in the problem

3.   Cover the symbol for the unknown value

4.   Write the formula you are going to use

5.   Put the given values in place of the symbols

6.   Solve the problem

Example:

If the voltage to a light bulb is 120 volts and the wattage is 60 watts, what is the current?

1.   P =
I =
E =

2.   P = 60 watts
I = _____ amps
E = 120 volts

3.  

4.   I = P/E

5.   I = 60/120

6.  I = 0.5 amps

If you want practice solving Watt’s Law problems, take a 5-question quiz by clicking the link  below.  You may check to see if you got the question right at the end of each question, or wait until you have completed all 5 questions to see how you did. Take the quiz more than once — there are many different questions.

Solve Watt’s Law Practice Problems