# 2 Part Kinematic Equation Problem

1. Sep 26, 2010

### demonslayer42

1. The problem statement, all variables and given/known data
A car driving at a constant speed of 75 ft/s passes a police car that is initially at rest. If the police car decides to give chase
A) What rate would the police have to accelerate to catch up with the other car in 12 seconds?
B) What is the police car's speed at the end of the 12 seconds?

2. Relevant equations
Use Kinematic Equations

3. The attempt at a solution
The first car's displacement would be 75 ft/s * 12 seconds = 900 feet? So if I use X = Vot + 1/2(at^2)that means that acceleration of the second car would have to be 12.50 ft/s Is this the correct? Or am I way off? So if the acceleration = 12.50 ft/s I use V = Vo + at and end up with Final V = 150 ft/s ? That just doesn't sound right to me, could you please try to explain what I'm doing wrong?

2. Sep 26, 2010

### Staff: Mentor

Looks good to me. You're doing nothing wrong.

3. Sep 26, 2010

### demonslayer42

Well thank you :) I'm trying really hard to learn Physics. It's difficult for me to learn, but it's very interesting.