Answer to Question #305443 in Physics for Cris

Question

A motorist traveling with a constant speed of 20.0 m/s passes a school-crossing corner, where the speed limit is 15.0 m/s. Just as the motorist passes, a police officer on a motorcycle at the corner starts off in pursuit with constant acceleration of 5.0 m/s^2. What is the total distance traveled by the motorist

Answer 1

$d_M=v_0t=20t$

$d_C=at^2/2=2.5t^2$

$d_M=d_C$

$20t=2.5t^2$

$t=8\:\rm s$

The total distance traveled by the motorist

$d_M=20*8=160\:\rm m$