In an oscillating spring, where is the
maximum acceleration achieved?
Answer:
At the maximum displacement
positions
When the spring is stretched and
released, what direction does the
spring force act?
Toward the equilibrium position
When the spring is stretched and
released, when is speed equal to 0?
Answer: at the point of maximum
displacement.
Often, the negative sign in Hooke’s
Law is ignored . . . Why is this
possible?
Answer: because the sign indicates
that the force and displacement are
in opposite direcitons
What are the units for k?
Answer: N/m
When using Hooke’s Law, what
units does the displacement value
need to be in?
Answer: meters
In an oscillating system, where is
the greatest kinetic energy located?
Answer: At the equilibrium positon
If the mass of a pendulum cut in
half, what happens to the period?
Answer: no change, mass does not
affect the period of a pendulum
If the length of a pendulum is
increased by 16 times, what
happens to the period?
Answer:
increases 4 times longer
If a pendulum clock keeps perfect
time at the base of a mountain, will
it also keep perfect time when
moved to the top of the mountain?
Why.
No, the gravity is slightly different
so the period will change also
The moon’s gravity is 1/6 of Earth.
If a mass spring system with a mass
of 2 kg has a period of 3 sec on
Earth, what will be the period on
the moon?
3 sec, gravity does not affect massspring systems.
If you know the cycles and time,
how do you find frequency?
Cycles divided by sec
Given period, how do you find
frequency?
1 divided by the period, they are
recipricals
If a grandfather clock is running
slow, how can you adjust the length
of the pendulum to correct the
time?
Shorten the length to shorten the
period
Problems
If a force of 50 N stretches a spring
.10 m, what is the spring constant?
500 N/m
A mass on a spring vibrates in
simple harmonic motion at an
amplitude of 8.0 cm. If the mass of
the object is .20 kg and the spring
constant is 130 N/m, what is the
frequency?
4.0 Hz
On the planet Xenos, an astronaut
observes that a 1.00 m long
pendulum has a period of 1.50 s.
What is the free-fall acceleration on
Xenos?
17.5
2
m/s
A pendulum goes past the
equilibrium position once every 2
seconds, what is frequency of the
pendulum?
.25 Hz