Electric Circuits
Name:
© The Physics Classroom, 2009
Page 1
Electric Potential Difference
Read from Lesson 1 of the Current Electricity chapter at The Physics Classroom:
http://www.physicsclassroom.com/Class/circuits/u9l1a.html
http://www.physicsclassroom.com/Class/circuits/u9l1b.html
http://www.physicsclassroom.com/Class/circuits/u9l1c.html
MOP Connection:
Electric Circuits: sublevels 2 and parts of 3
Review:
1. Electric field is defined as the aura about the space surrounding a charged object which exerts an
electrical influence upon other charged objects in that space. The direction of the electric field
vector is defined as the direction which a positive test charge would be accelerated. Potential
energy is the energy stored in an object due to the position of that object.
A Gravitational Analogy:
2.
Two diagrams are shown at the right.
In diagram A, a mass is held at an
elevated position. When let go of, the
mass falls from point A to point B.
In diagram B, the mass is originally at
point A and a person moves it back up
to point B.
For each diagram, indicate if work is
done by a non-conservative force in
moving the object from its initial
position (point A) to its position at point
B. Finally, indicate the position of
greatest gravitational potential energy.
Circle the answers in the space below
the diagrams.
Wnc done on mass:
Wnc done on mass:
Yes or No
Yes or No
Highest PE: A or B
Highest PE: A or B
3.
The following diagrams show an electric field and two points - labeled A and B - located within the
electric field. A positive test charge is shown at point A. For each diagram, indicate whether work
must be done upon the charge to move it from point A to point B. Finally, indicate the point (A or B)
with the greatest electric potential energy and the greatest electric potential (PE/charge).
Work done on test charge? Yes or No
Potential energy is greatest