|
Phys 4, Section 1
Exam 2
April 6, 2001
Š BAdL
= μoI
ΦB
= IBAdA
Wb
FB = qv x B =
IL x B
Emf = - dΦB/dt
V = vBL εo = 8.85
x 10-12
μo
= 4π
x 10-7
c2
= 1/(εoμo)
uE = εoE2/2
J/m3
uB = B2/(2μo)
|e-| = 1.6 x 10-19
C V = -L di/dt
L =
NΦB/i
H S = (E x B)/μo
W/m2
E = cB E = pc E = mc2
dp/dV
= (1/Ac)dp/dt
F = ma
= dp/dt
n1
sin θ1
= n2 sin θ2
sin θc
= n2/n1
1/s + 1/s' = 1/f 1/f = (n-1)(1/R1 -
1/R2)
f = R/2
m = -s'/s B = (μo/4π)(qv
x r)/r3
B = μoI/(2πr)
V = IR
P = FAv
P = I2R
F = qE k = 2π/λ
ω = 2πf f = 1/T
B = μoni
(inside solenoid)
1 T = 104
gauss
1. The magnitude of the emf induced in a loop by a changing magnetic
field B
perpendicular to it depends on
A) strength of B B) rate of change of B
C) direction of B
2. A proton moving with a constant velocity will generate
A) electric field B) magnetic
field C) e-m wave
D) first two E)
all three
3. The voltage developed across the 100 m wingspan of an airplane flying
at 400
km/hr through a vertically-down directed magnetic field of 0.5 gauss
is
A) 0.5 B) 1.0
C) 5.0 D) 10.0
E) 25
V
4. If the same current I = 15 A flows in opposite directions through two
long
parallel wires separated by 4.5 mm, what is the force between two
matched 4 m
segments?
A) 1 B) 2
C) 3 D) 4
E) 5
x 10-2
N
5. The idea of a displacement current was developed by
A) Gauss B) Ampere
C) Faraday D) Coulomb
E) Maxwell
6. A circular loop of wire is spread out on the floor. The South end of a
bar magnet
is moved down towards the center of the loop. What is the
direction of the induced
current in the loop as seen by a student looking
down at the loop?
A) CW B) CCW
7. A U-shaped conductor is held horizontally in a uniform magnetic field B
= 0.1 T
directed vertically downward. The width of the U is 4 cm, and a
metal rod placed
on the conductor parallel to the base of the U is pulled
away from the base at a
constant speed of 5.0 m/s. If the effective
resistance of the conductive loop (U and
rod) is 20 ohms, what is the force
required to keep the rod moving at constant
speed?
A) 1 B) 2
C) 3 D) 4
E) 5
x 10-6
N
8. Maximum flux flows through a loop in a magnetic field when the area A
of the
loop and the direction of B are
A) parallel B) perpendicular
C) 45o D) flux is independent of angle
9. A long thin solenoid has 400 turns per meter and radius 1.10 cm. The
current in
the solenoid is increasing at a uniform rate di/dt.
If the induced electric field at a
point near the center of the solenoid and
3.50 cm from its axis is 8.00 x 10-6 V/m,
what is di/dt?
A) 3.6 B) 4.8
C) 9.2 D) 12.3
E) 18.4
A/s
10. A tank whose bottom is a mirror is filled with water (n = 1.33) to a
depth of 20
cm. A small fish floats motionless 7.0 cm below the surface of
the water. What is
the apparent depth of the fish as determined from the
mirror image?
A) 3.5 B) 7.0
C) 10.5 D) 14.0
E) 24.8
cm
11. If the wavelength of visible light is approximately 0.5 micron, what
is the
frequency of visible light?
A) 106 B) 10-6
C)1014 D) 10-14
E) 1018
Hz
12. Who described light as a form of electromagnetic radiation?
A) Gauss B) Faraday
C) Ampere D)
Maxwell
13. If an electric field is represented by E = Emax sin(ωt
+ kx), which way is the
wave traveling?
A) in positive x-axis direction
B) in negative x-axis direction
C)
could be either
14. The phase relationship between the E-field and the B-field
in a traveling e-m
wave can be described as
A) in phase B) out of phase
C) in quadrature
[Note: The material involved in the next two questions will not
be required for
the 2002 exam.]
15. What kind of mirror can produce both real and virtual images of a
real object?
A) plane B) convex
C) concave
16. An object 8.0 cm high is placed 12.0 cm to the left of a converging
lens of focal
length 8.0 cm. What is the size of the image?
A) 2 B) 4
C) 8 D) 12
E) 16
cm
Answers: 1-b, 2-d, 3-a, 4-d, 5-e, 6-a, 7-d, 8-a, 9-c,
10-e, 11-c, 12-d, 13-b, 14-a, 15-c, 16-e
Last modified on April 03, 2002
| 
