# 13.6: Thinking about the material

- Page ID
- 19459

## Reflect and research

- What is an example of a system that is a simple harmonic oscillator (not covered in this this chapter)? What is the restoring force for that system?
- What happens to the motion of a mass-spring system in the presence of friction? Sketch out the position as a function of time.
- What is a “damped” harmonic oscillator?
- What is a coupled oscillator? Find a video of a coupled oscillator online and describe the motion.
- How do the shock absorbers on a car relate to simple harmonic motion?

## To try at home

- Compare values of \(\theta\) and \(\sin\theta\) to see when the small angle approximation holds. Does it matter if \(\theta\) is expressed in radians?
- Build a simple pendulum and describe the motion. Is it simple harmonic motion? Is it damped simple harmonic motion? Does the frequency depend on the length of the pendulum as expected?

## To try in the lab

- Theory lab: what is the function \(x(t)\) if there is a frictional force, proportional to velocity, \(-bv\), exerted on the spring mass system?
- Propose an experiment to test whether the period of the motion of pendulum depends on the amplitude of the motion.
- Propose an experiment to test whether a physical pendulum is well-described by simple harmonic motion.

Propose an experiment which measures the gravitational constant (\(G\)) using a torsion pendulum.