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Physics ~ Spring Final Review
Topics covered – Under each topic list laws and principles that apply. Write formulas and include
definitions of key words. The best review is to go over tests and quizzes, but the final
is not limited to those problems.
Ch. 11 - Harmonic Motion/Waves
Ch. 12 – Sound
Chs. 13 & 14 - Optics/Light
Ch. 16 – Electrostatics
Chs. 17 – Circuits
Ch. 19 – Magnetism
Ch. 22 – Radiation
Practice Problems
p. 397 #19, 21, 23, 27, 34, 35
p. 434 #20, 34, 36
p. 477 #20, 34, 51, 52
p. 581 #9, 16, 22, 26, 34
p. 627 # 35, 40, 41, 42, 70
p. 696 # 22, 26, 35
p. 820 # 10, 20, 21, 24
p. 514 # 14, 43, 45, 46
p. 667 #17, 18
p. 397 #19, 21, 23, 27, 34, 35
19)
f = 0.16 Hz
T=?
L=?
T = 1/f = 1/0.16 = 6.3 s
T = 2
21) k = 180 N/m
L/g
6.3 = 2
m = 1.5 kg
(L)/(9.8)
T=?
L = 9.8 m
f=?
a)
T = 2
m/k
T = 2
(1.5)/(180)= 0.57 s
f = 1/T = 1/0.57 = 1.8 Hz
23) Transverse waves move perpendicular to the medium it passes through
Longitudinal waves move parallel to the medium it passes through.
27) f = 3 Hz
T = 0.33 s
34)
a) A = 9 cm
b)  = 20.0 cm
c) T = 1/f = 1/25.0 = 0.04 s
d) v = /T = 0.20/0.04 = 5.0 m/s
35)
c = *f
3x108 = (9.00x109 ) = 0.033 m
p. 434 #20, 34, 36
20) The swing’s amplitude is maximized when the pushes match the swing’s natural frequency
34)
fn = n v/ 2L
f1 = (1)(274.4)/(2*0.31) = 442 Hz
f2 = 2*f1 = 884 Hz
f3 = 3*f1 = 1326 Hz
36) f1 = 320 Hz
v = 331 m/s
a) 320 = 331/(2*L)
b) f2 = 640 Hz
fn = n v/ 2L
L = 0.52 m
f3 = 960 Hz
p. 477 #20, 34, 51, 52
p. 514 #14, 43, 45, 46
20)
2
2 = 55o
o
35
35o
34)
55
35o
o
55o
R = 25.0 cm
1/di + 1/do = 1/f
M = - di/do
f = 12.5 cm
a) do = 45.0 cm
1/45.0 + 1/di = 1/12.5
di = 17.3 cm
M = -17.3/45 = -0.384  real, inverted
b) do = 25.0 cm
1/25.0 + 1/di = 1/12.5
-1.00  real, inverted
di = 25 cm
M = -25/25 =
di = -8.33
M = -(-8.33)/5= 1.67  virtual,upright
c) do = 5.00 cm
1/5.00 + 1/di = 1/12.5
51) R = - 11.3 cm (R is negative b/c mirror is convex. Convex b/c image is virtual & smaller)
M = 1/3
f = -5.65 cm
1/3 = -di/do
di = do/-3
by substitution:
14) noil = 1.48
do = ?
-3/do + 1/do = 1/-5.65
1
AIR
20
o
OIL
2
WATER
M = 2.00
do = ?
M=2
M = -di/do
1/di + 1/do = 1/f
2 = -di/do
di = -2do
by substitution:
1/di + 1/do = 1/f
do = 11.3 cm
n1 sin 1 = n2 sin 
nwater = 1.33
43) f = 15.0 cm
M = -di/do
-1/2do + 1/do = 1/15.0
1.00 sin 1 = 1.48 sin 
1 = 30.4o
1.48 sin = 1.33 sin 
2 = 22.3o
do = 7.5 cm
45) M = 2.00
do = ?
M = -di/do
1/di + 1/do = 1/f
a) f = 12.0 cm – converging lens
2 = -di/do
di = -2do
by substitution:
-1/2do + 1/do = 1/12.0
do = 6.0 cm
b) NOT POSSIBLE – diverging lens cannot produce a larger image
46) do = 80.0 cm
di = -40.0 cm (negative b/c image is in front of lens)
1/di + 1/do = 1/f
1/-40.0 + 1/80.0 = 1/f
f=?
f = -80.0 cm
p. 581 #9, 16, 22, 26, 34
9) The signs of the charge determine the direction of electric force
16) q1 = +2.5 C = 2.5x10-6 C q2 = -5.0 C = -5.0x10-6 C
r = 5.0 cm = 0.05 m
Fe = k*q1*q2/r2 = 8.99x109(2.5x10-6)(5.0x10-6)/0.052 = 45 N - attractive
22) electric field – a region of space around a charged object in which there exists electric forces
26) The number of electric field lines is determined by the strength of the electric field. The
direction of the lines is determined by the sign of the charge. Electric field lines start at a
positive charge and end at a negative charge.
39) q = e*N
q = q+ + q-
q+ = (1.6x10-19)(7.0x1013) = 1.12x10-5 C
1.12x10-5 + -6.4x10-6 C =
p. 627 # 35, 40, 41, 42, 70
35)
q- = (-1.6x10-19)(4.0x1013) = -6.4x10-6 C
4.8 x 10-6 C
p. 667 #17, 18
(c) has the greatest resistance. It is the longest w/ the narrowest diameter.
(a) has the least resistance. It is the shortest w/ the widest diameter.
40) I = V/R
R = 15 
I = 3.0/15 = 0.2 A
V = 3.0 V
I=?
41) R = V/I
V = 12 V
I = 0.40 A
R=?
V = 9.0 V
I=?
R = 12/0.40 = 30 
42) I = V/R
a) R = 5.0 
I = 9.0/5.0 = 1.8 A
b) R = 2.0 
I = 9.0/2.0 = 4.5 A
c) R = 20.0 
I = 9.0/20.0 = 0.45 A
70) I = 2.0x105 A
t = 0.50 s
I = C/t
C = I*t = (2.0x105)(0.50) = 100 000 C
17)
4.0 
a) Req = R1 + R2 + R3 = 4.0 + 8.0 + 12 = 24 
b) I = V/Req = 24/24 = 1.0 A
8.0 
24 V
12 
18)


a) Req = 2.2 
b) I = 10.9 A
p. 696 # 22, 26, 35
22) By the right hand rule, the direction of the magnetic force is up; the proton will move UP.
The magnetic force on an electron is in the opposite direction; an electron would move DOWN
26)
a) INTO THE PAGE
b) RIGHT
c) DOWN
35)
a) LEFT
b) INTO THE PAGE
c) OUT FROM THE PAGE
d) UP
p. 820 # 10, 20, 21, 24
10)
alpha () – weakest (blocked by paper/skin)
X  -4Y + 4He
-2
releases an APLHA PARTICLE
2
beta () – “mid-strength” (don’t block w/ lead  generates  radiation)
X  +1Y + - + 
releases an ELECTRON & ANTINEUTRINO
- = -1e
gamma () – strongest (blocked by lead)
X  X + 
20)

releases a photon (energy)
10
B
5
4
21)
a)
4
He
b)
2
24) N = 0.0625 No
He
2
T½ = 5730
=?
t=?
T ½ = 0.693/  = 0.00012
N = Noe(-*t)
0.0625No = Noe(-*t)
t = 23 104 years old