Question

a police officer parked on the side of the rode clockes a driver at a constant 130km/h (passing the stopped car). if the officer can accelerate at 12 km/h/s, how long will it take her to catch up to the car? how fast will the polive officer be going as she comes even with the car?

Answer 1

given,

speed of the vehicle = 130 Km/h

officers accelerates at = 12 km/h/s

time taken by the driver to catch the vehicle = ?

at time t second

`130 t = (1)/(2)at^2`

`260 t - 12 t^2 = 0`

t (12 t - 260 )= 0

12 t = 260

t = 21.67 s

v = u + at

v = 12 × 21.67

v = 260 Km/h