A charge of #5 C# is passing through points A and B on a circuit. If the charge's electric potential changes from #27 J# to #7 J#, what is the voltage between points A and B?

1 Answer
Mar 10, 2016

Answer:

#4V#

Explanation:

We use the definition of electrical potential, or Voltage as given by

#V=(Delta E)/Q#

where #V# is the voltage change between two locations, #Delta E# is the change in potential energy and #Q# is the charge that is moving. The change in potential energy in going from A to B (final state being at point B):

#Delta E=7J-27J=-20J#

Then the voltage at B with respect to A is

#V_B=(-20J)/(5C)=-4V#

Therefore, the voltage at point B is #4V# lower than the voltage at point A.