Physics 152
Final Exam
_
_
(Name)
1.
Find the force on a charge on q1 = 4x10-6coulombs at the apex
of an equilateral triangle with -6
sides of 20 cm. if the other two
corners are occupied by q2=+3x10 coulombs and q3=-5x10-6coulombs
respectively. (Specify
You are allowed to work together; however, your answers should not be carbon-copies of each other work. SHOW ALL
YOUR WORK! For full credit, provide explanations when requested. This exam will count as 50 points (half of the value of
an in-class exam).
28.11
The energy of the emitted photon is
E =
hc
626
( 6. 10
34
=
J s) ( 2. 108 m s) 1 nm
998
9
656 nm
10 m
1 ev
1. 1019
602
89
= 1. eV
J
This photon energy is also the difference in the electrons energy in its initial and
final orbits. The energies of
Physics 152
Exam 4
_
(Name)
1.
A particular subatomic particle has an expected lifetime
(average value) of 2 x 10-7 seconds when it at rest or moving
slowly. Its rest mass is 80 times as massive as an electrons.
When it emitted from a nucleus in a particu
Physics 152
Sample exam 2
1.
A small light rests on the bottom of a swimming pool 1.6 meters deep.
Though the light radiates uniformly in all directions, from above the
light emerging from the water (n=1.34) surface forms a circle. What is
the diameter of
t
p
3. s
0
26.3
t= t =
p
26.4
(a) Observers on Earth measure the time for the astronauts to reach Alpha
Centauri as t = 4. yr . But these observers are moving relative to the
42
E
1 ( v c)
2
=
1-( 0. )
80
2
= 5. s
0
astronauts internal biological clock an
19.1
The direction in parts (a) through (d) is found by use of the right hand rule. You
must remember that the electron is negatively charged and thus experiences a
force in the direction exactly opposite that predicted by the right hand rule for a
positi
1-20.23
(a) To oppose the motion of the magnet, the magnetic field generated by the
induced current should be directed to the right along the axis of the coil. The
ef o i
current must then be l tt r ght through the resistor.
(b) The magnetic field produce
Units! kiiograms, meters, amps (l), teslas (T), torque cfw_Nam, kilo, milli, micro, nano; pa = 41: x107 T-m/A
I. An electron g = 1.6 x 10 C) is traveling east (+x) with an instantaneous velocity of
2.5 x 105 refs when it enters a uniform magnetic eld B of
Phys 152 Exam 1 Practice Problem
CH15
1. Experimental evidence indicates that . a
A) charge is quantized and conserved. Wt aura-'5; oi? )Cii
B) charge is quantized but not conserved.
C) charge is conserved but not quantized.
D). charge is neither quantize
Phys 152 Fall 2016 Exam 1 Name k6?)
1. A particular nucleus of the element plutonium contains 94 protons and 150 neutrons. What is the
magnitude of the force from the nucleus (11;) on a single elect on (12) that Is at a distance of
ti: 0. 563 x 10 In from
23.7
The radius of curvature of a concave mirror is positive, so R = + 20. cm . The
0
mirror equation then gives
0
0
121
1
1 p 10. cm
( 10. cm ) p
=
=
, or q =
q R p 10. cm p ( 10. cm ) p
0
0
p 10. cm
0
(a) If p = 40. cm , q = + 13. cm and M =
0
3
q
13.
24.3
(a) The distance between the central maximum and the first order bright fringe
L
ybright
=
is y = ybright
, or (Note, it is safer to not use the
m =1
m =0
d
approximation used here that tan=sin)
y =
L
d
1
( 546. 10
=
9
20
) (1. m ) = 2. 10
62
m
3
3
27.1
From Wiens displacement law,
(a)
T=
0.
2898 102 m K
m ax
=
0.
2898 102 m K
970 109 m
= 2. 103 K ,or 3000 K
99
(b) T =
0.
2898 102 m K
m ax
=
0.
2898 102 m K
145 109 m
= 2. 104 K ,or 20000 K
00
27.5
E = hf =
hc
which yields
(a)
E=
63
( 6. 10
34
=
E=
25.9
This patient needs a lens that will form an upright, virtual image at her near
point (60.0 cm) when the object distance is p = 24. cm . From the thin lens
0
equation, the needed focal length is
f=
25.12
0
0
pq ( 24. cm ) ( 60. cm )
=
= + 40. cm
0
p+
Physics 152
Exam 4
Summer 1997
_
(Name)
1. A" mission controller" and a pilot are both planning a space
trip to and from a distant star. The controller has had training
only in classical physics and doesn't know about time dilation.
He recommends taking s