View Single Post
Jan17-12, 01:47 PM
P: 9
1. The problem statement, all variables and given/known data

Two train cars are on a straight, horizontal track. One car starts at rest and is put in motion with a constant acceleration of 2.1 m/s2. This car moves toward a second car that is 25 m away and moving at a constant speed of 3.6 m/s.

(a) Where will the cars collide?
(b) How long will it take for the cars to collide?

2. Relevant equations

x= x0 + V0*t
x= 1/2(a)*t^2 + V0*t + x0

3. The attempt at a solution

This is a practice problem from WebAssign for our Physics course. My friend and I could not figure out how to solve this problem but we know the answer for both the parts which doesn't help since we don't know how to do the problem. If someone could help! Thanks!

a) 49.8 m
b) 6.89 s
Phys.Org News Partner Science news on
Sapphire talk enlivens guesswork over iPhone 6
Geneticists offer clues to better rice, tomato crops
UConn makes 3-D copies of antique instrument parts