During a football game, A is 8.0 m behind B and is running at 7.0 m/s when B catches the ball and starts to accelerate away at 2.8 m/s(squared) from rest.
a) Will A catch B? If so, after how long?
b) How far down the field will B have run?
Assuming B was at a standstill, then to catch her, they must travel the same distance in the same time.
dA=-8+7t
dB=1/2 2.8 t^2
setting them equal, see if you can get a time...
-8+7t=1.4t^2
put it in quadratic form, and solve for t. If you get a positive t, then they meet