Physics Question (2nd request)?

Question

When seven people whose average mass is 86 kg sit down in a car they find that the car drops 0.98 cm lower on its springs. Then they get out of the car and bounce it up and down. What is the frequency of the cars vibration if its mass (empty) is 3743 kg (in Hz). Acceleration of gravity is 98.8 m/s^2.

Answer 1

From the first part of the data , you can calculate the spring constant.
The weight of the seven persons = k*x. This gives
k = 7*m*g/x. Make sure that you use MKS units throughout.
The frequency of oscillation is given by
f = (1/2*pi)*sqrt(k/m).
Here of course you have to use the mass of the empty car.