PHYSICS HELP A sports car speeds past a stationary police car at 100 km/hr in a 50

D

Dude

New member
km/hr zone...? A sports car speeds past a stationary police car at 100 km/hr in a 50 km/hr zone. The
police officer immediately takes off in pursuit, accelerating at 8 m/s2.
a) How far will both cars travel before the police officer catches the speeder? (Hint: write
separate equations for the distance traveled by both the sports car and the police car,
then think about what needs to happen with distance and time for each for the police car
to catch the sports car.)
b) How fast will the police car be moving when it catches up to the speeder?


The answer is: a)191.8 m b) 55.4 m/s
 
For a sports car :
x1 = V1 t
for police car :
x2 = (1/2) a t^2
let
x1 = x2 --> V1 t = (1/2) a t^2 --> t = 2 V1/a
x = 2 (V1^2)/a = 2 (100/3.6)^2 /8 = 192.9 m
v2 = a*t = 2 V1 = 200 km/h = (200/3.6) = 55.5 m/s
 
Back
Top