2 football players who are 20m apart run towards each other. Player 1 runs at 6m/s, his acceleration is 0. Player 2 starts from rest and he accelerates at 4.0m/s When do they collide?
We can solve this problem using a kinematic equation.
Let `d_1` = distance travelled by player 1
Let `d_2` = distance travelled by player 2
`d_2 = v_(i2)t+0.5a_2t^2`
When the two meet, they will have together travelled 20m:
Therefore, t=-5 and t=2
Since time cannot be negative, they will meet after they have run for 2 seconds at which point:
Player 1 will have run 12m and player 2 will have run 8m.