Transcript Potential - UCF Physics
4.1
Exam Date – Wed 2/9
Topics Covered Listed on Class Website Sample Exam from a few years back is also on the web.
Today
Start Unit 5: Electric Potential (Energy Methods)
Wednesday
Monday
More of the same
Friday: Surprise – Quiz #2 (for real!)
Spring Break is just a few weeks away – (5ish)
The figure shows the electric field lines in the vicinity of two point charges. Which one of the following statements concerning this situation is true?
A)
q
1 is negative and
q
2 is positive.
B) The magnitude of the ratio (
q
2 /
q
1 ) is less than one.
C) Both
q
1 and
q
2 have the same sign of charge.
D) The magnitude of the electric field is the same everywhere.
E) The electric field is strongest midway between the charges.
A cubical Gaussian surface is placed in a uniform electric field as shown in the figure. The length of each edge of the cube is 1.0 m. The uniform electric field has a magnitude of 5.0 × 10 8 N/C and passes through the left and right sides of the cube perpendicular to the surface. What is the total electric flux leaving the cubical Gaussian surface?
A) 5.0 × 10 8 m 2 /C B) 3.0 × 10 9 N×m 2 /C C) 2.5 × 10 6 N×m 2 /C D) 1.5 × 10 7 N×m 2 /C E) zero N×m 2 /C
What is the electric flux passing leaving a Gaussian surface that surrounds a +0.075 C point charge?
A) 8.5 × 10 9 N×m 2 /C B) 6.8 × 10 8 N×m 2 /C C) 1.3 × 10 7 N×m 2 /C D) 4.9 × E) 7.2 × 10 6 N×m 2 /C 10 5 N×m 2 /C
q inside
e 0 e 0= 8.85×10 −12 SI Units
A solid, conducting sphere of radius charge of +6
a
carries an excess µ C. This sphere is located at the center of a hollow, conducting sphere with an inner radius of
b
and an outer radius of
c
as shown. The hollow sphere also carries a total excess charge of +6 µ C.
Determine the excess charge on the
outer surface
of the outer sphere (a distance
c
from the center of the system).
A) zero coulombs B) – 6 m C C) +6 m C D) +12 m C E) – 12 m C
+
Mrs. Field Mr. External
Mrs. Field Mr. External
E
That was HARD WORK Mr. External
+ charge
Sure Was Mrs. Fields Mrs. Field Mr. External
Each does the negative amount of work that the other one does.
Constant Speed
The net work done by a conservative (field) force on a particle moving around a closed path is
ZERO!
The work necessary for an external agent to move a charge from an initial point to a final point is INDEPENDENT OF THE PATH CHOSEN!
A conservative force is NOT a Republican.
An External Agent is NOT 007.