Name: ________________________ Class: ___________________ Date: __________
ID: A
Exam 2
Multiple Choice
Identify the choice that best completes the statement or answers the question.
____
____
____
1. In the circuit of your house, what happens to the voltage to each electrical device as you add more
appliances?
a. the voltage increases
c. the voltage decreases
b. the voltage stays the same
d. none of these
2. What does GFCI do?
a. protects you from magnetic fields
c. checks if Iin>Iout
b. turns off the circuit if the current exceeds d. provides a clear path to ground
a certain amount
3. Two resistors are connected in series to an ideal battery with V= 6 V. One of the resistors is twice
the resistance of other resistor. What is the potential across the bigger resistor?
____
a. 3 V
c. 2 V
b. 6 V
d. 4 V
4. This figure shows the velocity vector of an electron as it enters a magnetic field. What is the direction of the
force experienced by the electron?
a.
b.
c.
down
into the page
right
d.
e.
1
left
out of the page
Name: ________________________
____
____
____
ID: A
5. A positively charged particle enters a magnetic field as shown. What is the direction of the force the particle
experiences?
a. Out of the page
c. Down
b. Into the page
d. Up
6. This figure shows 3 configurations of three wires, which are either going into or coming out of the page.
Which configuration produces a net magnetic field with the largest magnitude at the point p, which is
equidistant from each of the three wires?
a. A
c. C
b. B
d. All the same
7. Which photon from the following portions of the electromagnetic spectrum has the lowest energy?
a.
b.
ultra-violet light
gamma-rays
c.
d.
2
Visible light
x-rays
Name: ________________________
ID: A
____
8. Which of the following is true?
____
a. n1>n2
c. n1=n2
b. n1<n2
d. Not enough information
9. Which of these phenomena reflect the wave nature of light?
I. Reflection
II. Refraction
III. Interference
IV. Photoelectric effect
a. III & IV
d. I
b. II
e. I & IV
c. II & III
____ 10. In this image, a man is preparing to shoot the fish with his handgun. The actual position of the fish is shown.
Should the man aim above or below the position where he sees the fish?
a.
b.
above
below
c.
d.
3
directly at the fish he sees
none of these
Name: ________________________
ID: A
Problem
11. The wire shown in this figure lies in a uniform magnetic field. Each straight section is 1.5 m long
and makes angles θ1=45º and θ2=30º with the x-axis. The current in the wire is 3 A. What is the net
magnetic force on the wire if the magnetic field is 2.0k̂ T?
.
4
Name: ________________________
ID: A
r
12. An electron moves through a magnetic field given by B = 3Bx ˆj . At a particular instant, the electron
has a velocity of 10.0 ˆj + 12kˆ m/s and the magnetic force acting on it is ( 3.2 ×10 −20 N) iˆ . Find Bx .
.
5
Name: ________________________
ID: A
13.
This figure represents a simplistic optical fiber: a plastic core (n 1=1.45) is surrounded by a plastic
sheath (n2=1.40). A light ray is incident on one end of the fiber at angle θ. The ray is to undergo
total internal reflection at point A, where it encounters the core-sheath boundary. (Thus there is
no loss of light through that boundary.) What is the maximum value of θ that allows total internal
reflection at A?
.
6
Name: ________________________
ID: A
14. In this figure, what value must R have if the current in the ciruit is to be 3.0 A? Take ε 1 = 4.0 V,
ε 2 = 5.0 V, and r 1 = r 2 = 2.0 Ω .
What is the rate at which thermal energy appears in R?
.
7
Name: ________________________
ID: A
15. In this figure, R 1 = 100 Ω , R 2 = R 3 = 300 Ω , R 4 = 400 Ω , and ε = 20 V .
What is the equivalent resistance? ________
What is the current in R 1?________
What is the current in R 2?________
What is the current in R 3? ________
What is the current in R 4? ________
.
8
ID: A
Exam 2
Answer Section
MULTIPLE CHOICE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
B
C
D
D
A
D
C
A
C
B
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
PTS:
1
1
1
1
1
1
1
1
1
1
PROBLEM
11. ANS:
.
PTS: 1
12. ANS:
.
PTS: 1
13. ANS:
.
PTS: 1
14. ANS:
.
PTS: 1
15. ANS:
.
PTS: 1
1