Physics 236 Worksheet: Chapter 25, Electric Potential

1.     The potential difference between points A and B is defined as:

a.     The force required to move a unit charge from A to B.

b.      The work required to move a unit charge from A to B.

c.      The electric charge at A minus the electric charge at B.

d.     The electric field at A minus the electric field at B.

2.     Which of the following statements is true?

a.     Electric field is a vector and potential is a scalar.

b.      Electric field is a scalar and potential is a vector.

c.      Electric field and potential are both vectors.

d.     Electric field and potential are both scalars.

3.     When a negative charge moves from a point of higher potential to a lower potential it

a.     gains potential energy.

b.      loses potential energy.

c.      undergoes no change of potential energy.

4.     A volt is the same as a

a.     N/C

b.      J/N

c.      W/s

d.     J/C

5.     The eV is a unit of

a.     potential

b.      electric field

c.      energy

d.     charge

6.     In which region(s) is there a position on the axis at which the potential is zero?

a.     Region I only.

b.      Region II only.

c.      Region III only.

d.     Regions I and II but not III.

e.     Regions I and III but not II.

f.       Regions II and III but not I.

g.      All regions.

h.     No regions.

7.     Which of the following statements is not true about equipotential lines?

a.     They begin on positive charges and end on negative.

b.      The potential is the same at any point on a line.

c.      They are perpendicular to electric field lines.

d.     Different lines at different places in a drawing may not represent the same potential.

 

Ans: 1-b, 2-a, 3-a, 4-d, 5-c, 6-d, 7-a

 

 

Physics 236 Worksheet: Chapter 25, Electric Energy and Potential

1.     If the distance between two positive charges is doubled, their electrical potential energy will

a.     be doubled.

b.      be cut in half.

c.      be increased by a factor of four.

d.     be decreased by a factor of four.

2.     If the distance between a positive charge and a negative charge is doubled, their electrical potential energy will

a.     be doubled.

b.      be cut in half.

c.      be increased by a factor of four.

d.     be decreased by a factor of four.

3.     The expression                      is used to calculate

a.     the electric field at B minus the electric field at A.

b.      the force required to move a unit charge from A to B.

c.      the electric energy of two charges at A and B.

d.     the difference of potential between A and B.

4.     The difference of potential between any two points inside of a charged conducting sphere is

a.     directly proportional to the distance between the points.

b.      inversely proportional to the distance between the points.

c.      zero.

5.     The expression               is used to calculate

a.     the electric potential at point x.

b.      the potential difference between two points separated by a distance x.

c.      the magnitude of the electric field at point x.

d.     the x-component of the electric field.

6.     Electron A is accelerated from rest through a potential difference V. Electron B is accelerated from rest through a potential difference of 2V. This takes place in a vacuum.

a.     Electron B will have a final velocity twice that of A.

b.      Electron B will have a final velocity four times that of A.

c.      Electron B will have a final velocity            that of A.

d.     This cannot be determined without knowledge of either the distance or time involved.

7.     An electron and a proton are released midway between two equally and oppositely charged plates. This takes place in a vacuum.

a.     The electron will strike the positive plate before the proton has reached the negative plate.

b.      The electron will strike the positive plate after the proton has reached the negative plate.

c.      The electron will strike the positive plate at the same time the proton reaches the negative plate.

8.     An electron and a proton are released midway between two equally and oppositely charged plates. This takes place in a vacuum. When they reach their respctive plates

a.     the electron will have more kinetic energy than the proton.

b.      the proton will have more kinetic energy than the electron.

c.      both will have the same kinetic energy.

 

Ans: 1-b, 2-b, 3-d, 4-c, 5-d, 6-c, 7-a, 8-c