Quiz Review

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 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 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 mass-spring 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 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 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 m/s2

A pendulum goes past the equilibrium position once every 2 seconds, what is frequency of the pendulum?

.25 Hz