# Simple Harmonic Motion and Resonance

1. May 5, 2012

### Gyoung68

1. The problem statement, all variables and given/known data
A car with mass 1220kg including the driver travels over a bridge with expansion gaps spaced 5.5m apart. At a speed of 12.0m/s, the car bounces up and down with exceptionally large amplitude. Two more 80kg passengers now get in the car. a) What speed will result in maximum oscillation amplitude? b) How much did the car's suspension sag with the two added passengers? c) What kind of oscillation behavior results from the car's suspension

2. Relevant equations
Something dealing with wavelength, wave speed, and mass

3. The attempt at a solution
Not a clue

2. May 5, 2012

### ehild

The answer is in the title of your post. The car is suspended - on what?

http://www.carbibles.com/suspension_bible.html

So it performs SHM in vertical direction. It gets some bump whenever it drives through the expansion gaps. What is the time elapsed between these bumps? What happens when a vibrating body is pushed periodically?

ehild