# Air Resistance of a car

1. Nov 18, 2005

### Izekid

The Air Resistance of a car grows proportional to the square of the velocity. On a certain car is the air resistance 0,18kN when the velocity is 54km/h.

So the problem is ..

What is the air resistance when the velocity is 90 km/h?

How high is the velocity when the air resistance is 0,30kN?

I don't understand how to do this please help me...

2. Nov 18, 2005

### Staff: Mentor

Write an equation which gives the relatioship for Air Resistance and the square of velocity.

Then solve for the constant since one is given a value for air resistance and the corresponding velocity.