Simple Harmonic Motion Problem Solving (pendulum, mass on a spring)

Examples of solving simple harmonic motion problems.

0:00 - Intro
0:37 - Problem 1
5:52 - Problem 2
8:07 - Problem 3

Problem 1 - Having landed on a newly discovered planet, an astronaut sets up a simple pendulum of length 0.7 m and finds that it makes 120 complete oscillations in 446 s. What is the gravitational acceleration on the surface of this planet?

Problem 2 - When a mass of 25 g is attached to a certain spring, it makes 20 complete vibrations in 4.0 s. What is the spring constant of the spring?

Problem 3 - The body of a 1275 kg car is supported on a frame by four springs. The spring constant of a single spring is 2x10^4 N/m. Four people riding in the car have a combined mass of 255 kg. When driven over a pothole in the road, the frame vibrates and for the first few seconds the vibration approximates simple harmonic motion. What is the period of vibration of the car?