AP Physics Review Ch 10 – Oscillatory Motion
 Simple Harmonic Motion  repetitive motion that follows Hooke’s Law; Fs = -kx
 Know where net force, acceleration, and speed are maximum values and where they are zero; be able
to calculate the maximum values for a mass oscillating on the end of a spring (conservation of
mechanical energy for speed, Hooke’s law for force, and Newton’s 2 nd law for acceleration)
 Understand the position versus time graph for an object oscillating with SHM
𝑥 = 𝐴 cos 𝜔𝑡
𝐴amplitude
𝜔=
2𝜋
𝑇
= 2𝜋𝑓
 Understand the energy transformations for an object oscillating with SHM; be able to use conservation
of mechanical energy to calculate speed or amplitude
𝐸𝑚𝑒𝑐ℎ = 𝐾 + 𝑈
and
𝐾=0
@
𝐴 (amplitude)
so
1
𝐸𝑚𝑒𝑐ℎ = 𝑘𝐴2
2
 Understand the graphs for energy and force with respect to position for an object undergoing SHM
 Understand the motion of a simple pendulum at small angles; be able to use conservation of mechanical
energy to find speed of a simple pendulum at the bottom of the swing; be able to use Newton’s 2 nd law to
determine the tension in the string at the bottom of the swing knowing that the acceleration is centripetal
 Know the factors that affect the period (or frequency) of a spring and pendulum
𝑇𝑆 = 2𝜋
𝑚
𝑘
𝑇𝑃 = 2𝜋
𝑙
𝑇=
𝑔
1
𝑓
 Understand everything we have covered this year in physics including projectile motion, Newton’s laws
(calculate force and acceleration), conservation of energy, conservation of momentum, and circular motion
Slide 10-1
This is the position graph of
a mass on a spring. What
can you say about the speed
and the magnitude of the net
force at the instant indicated
by the dotted line?
A. Speed is a maximum; net force is zero.
B. Speed is zero; net force is zero.
C. Speed is a maximum; net force is a maximum.
D. Speed is zero; net force is a maximum.
This is the position graph of
a mass on a spring. What
can you say about the speed
and the magnitude of the net
force at the instant indicated
by the dotted line?
A. Speed is a maximum; net force is zero.
B. Speed is zero; net force is zero.
C. Speed is a maximum; net force is a maximum.
D. Speed is zero; net force is a maximum.
A mass oscillates on a horizontal spring. It’s velocity is vx
and the spring exerts force Fx. At the time indicated by the
arrow,
A.
B.
C.
D.
E.
vx is  and Fx is 
vx is  and Fx is –
vx is – and Fx is 0
vx is 0 and Fx is 
vx is 0 and Fx is –
Slide 14-4
A mass oscillates on a horizontal spring. It’s velocity is vx
and the spring exerts force Fx. At the time indicated by the
arrow,
A.
B.
C.
D.
E.
vx is  and Fx is 
vx is  and Fx is –
vx is – and Fx is 0
vx is 0 and Fx is 
vx is 0 and Fx is –
Slide 14-5
A mass oscillates up and
down on a spring; the motion
is illustrated at right.
1. At which time or times shown is the acceleration
zero?
2. At which time or times shown is the kinetic energy
a maximum?
3. At which time or times shown is the potential energy
a maximum?
.
Slide 14-6
A mass oscillates up and
down on a spring; the motion
is illustrated at right.
1. At which time or times shown is the acceleration
zero? A, C, E
2. At which time or times shown is the kinetic energy
a maximum? A, C, E
3. At which time or times shown is the potential energy
a maximum? B, D
Slide 14-7
A mass on a spring in SHM has amplitude A and period T.
At what point in the motion is v = 0 and a = 0
simultaneously?
(A) x = A
(B) x > 0 but x < A
(C) x = 0
(D) x < 0
(E) none of the above
Slide 10-8
A mass oscillates in simple harmonic motion with
amplitude A. If the mass is doubled, but the amplitude
is not changed, what will happen to the total energy of
the system?
(A) total energy will increase
(B) total energy will not change
(C) total energy will decrease
Slide 10-9
If the amplitude of a simple harmonic oscillator is
doubled, which of the following quantities will change
the most?
(A) frequency
(B) period
(C) maximum speed
(D) maximum acceleration
(E) total mechanical energy
Slide 10-10
Two identical blocks oscillate on different horizontal
springs. Which spring has the larger spring constant?
A. The red spring
B. The blue spring
C. There’s not enough
information to tell.
Slide 14-11
Two identical blocks oscillate on different horizontal
springs. Which spring has the larger spring constant?
A. The red spring
B. The blue spring
C. There’s not enough
information to tell.
Slide 14-12
A block of mass m oscillates on a horizontal spring with
period T  2.0 s. If a second identical block is glued to the
top of the first block, the new period will be
A.
B.
C.
D.
E.
1.0 s
1.4 s
2.0 s
2.8 s
4.0 s
Slide 14-13
A block of mass m oscillates on a horizontal spring with
period T  2.0 s. If a second identical block is glued to the
top of the first block, the new period will be
A.
B.
C.
D.
E.
1.0 s
1.4 s
2.0 s
2.8 s
4.0 s
Slide 14-14
A glider with a spring attached to each end oscillates with a
certain period. If identical springs are added in parallel to the
original glider, what will happen to the period?
(A) period will increase
(B) period will not change
(C) period will decrease
Slide 10-15
A mass oscillates on a vertical spring with period T.
If the whole setup is taken to the Moon, how does the
period change?
(A) period will increase
(B) period will not change
(C) period will decrease
Slide 10-16
A pendulum is pulled to
the side and released.
The mass swings to the
right as shown. The
diagram shows positions for half of a complete oscillation.
1. At which point or points is the speed the highest?
2. At which point or points is the acceleration the
greatest?
3. At which point or points is the restoring force the
greatest?
Slide 14-17
A pendulum is pulled to
the side and released.
The mass swings to the
right as shown. The
diagram shows positions for half of a complete oscillation.
1. At which point or points is the speed the highest? C
2. At which point or points is the acceleration the
greatest? A, E
3. At which point or points is the restoring force the
greatest? A, E
Slide 14-18
A series of pendulums with different length strings and different
masses is shown below. Each pendulum is pulled to the side by
the same (small) angle, the pendulums are released, and they
begin to swing from side to side.
Which of the pendulums oscillates with the highest frequency?
Slide 14-19
A series of pendulums with different length strings and different
masses is shown below. Each pendulum is pulled to the side by
the same (small) angle, the pendulums are released, and they
begin to swing from side to side.
A
Which of the pendulums oscillates with the highest frequency?
Slide 14-20
Two pendula have the same length, but different masses
attached to the string. How do their periods compare?
(A) period is greater for the greater mass
(B) period is the same for both cases
(C) period is greater for the smaller mass
Slide 10-21
Two pendula have different lengths: one has length L
and the other has length 4L.
How do their periods compare?
(A) period of 4L is four times that of L
(B) period of 4L is two times that of L
(C) period of 4L is the same as that of L
(D) period of 4L is one-half that of L
(E) period of 4L is one-quarter that of L
Slide 10-22
A grandfather clock has a weight at the bottom of the
pendulum that can be moved up or down. If the clock
is running slow, what should you do to adjust the time
properly?
(A) move the weight up
(B) move the weight down
(C) moving the weight will not matter
(D) call the repair man
Slide 10-23
A swinging pendulum has period T on Earth. If the
same pendulum were moved to the Moon, how does
the new period compare to the old period?
(A) period increases
(B) period does not change
(C) period decreases
Slide 10-24
After a pendulum starts swinging, its amplitude
gradually decreases with time because of friction.
What happens to the period of the pendulum during
this time?
(A) period increases
(B) period does not change
(C) period decreases
Slide 10-25
What is the spring constant of a spring that stretches 2.00 cm
when a mass of 0.600 kg is suspended from it? Use 9.8 m/s2
for gravity.
(A) 0.300 N/m
(B) 30.0 N/m
(C) 2.94 N/m
(D) 294 N/m
A 0.50-kg mass is attached to a spring of spring constant 20 N/m
along a horizontal, frictionless surface. The object oscillates in
simple harmonic motion and has a speed of 1.5 m/s at the
equilibrium position. What is the amplitude of vibration?
(A) 0.024 m
(B) 0.058 m
(C) 0.24 m
(D) 0.58 m
A 2.0-kg mass is attached to the end of a horizontal spring
of spring constant 50 N/m and set into simple harmonic
motion with an amplitude of 0.10 m. What is the total
mechanical energy of this system?
(A) 0.020 J
(B) 25 J
(C) 0.25 J
(D) 1.0 J
A 4.0-kg object is attached to a spring of spring constant 10 N/m.
The object is displaced by 5.0 cm from the equilibrium position
and let go. What is the period of vibration?
(A) 2.0 s
(B) 4.0 s
(C) 8.0 s
(D) 16 s
A pendulum has a period of 2.0 s on Earth.
What is its length?
(A) 2.0 m
(B) 1.0 m
(C) 0.70 m
(D) 0.50 m
The pendulum of a grandfather clock is 1.0 m long.
What is its period on the Moon where the acceleration
due to gravity is only 1.7 m/s2?
(A) 1.2 s
(B) 2.4 s
(C) 4.8 s
(D) 23 s
A block oscillates on a very long horizontal spring. The
graph shows the block’s kinetic energy as a function of
position. What is the spring constant?
A.
B.
C.
D.
1 N/m
2 N/m
4 N/m
8 N/m
Slide 14-32
A block oscillates on a very long horizontal spring. The
graph shows the block’s kinetic energy as a function of
position. What is the spring constant?
A.
B.
C.
D.
1 N/m
2 N/m
4 N/m
8 N/m
Slide 14-33
A set of springs all have initial length 10 cm. Each spring now
has a mass suspended from its end, and the different springs
stretch as shown below.
Now, each mass is pulled down by an additional 1 cm and
released, so that it oscillates up and down. Which of the
oscillating systems has the highest frequency?
.
Slide 14-34
A set of springs all have initial length 10 cm. Each spring now
has a mass suspended from its end, and the different springs
stretch as shown below.
C
C
Now, each mass is pulled down by an additional 1 cm and
released, so that it oscillates up and down. Which of the
oscillating systems has the highest frequency?
Slide 14-35