Question

A policeman is chasing a pickpocketer. The pickpocketer crosses a bus stop at a speed of 18 kmh−1 and the policeman crosses the bus stop 20 s later. Assuming that they travel at constant speeds, how far from the bus stop will the policeman catch the pickpocketer?

Answer 1

Answer:

put the value and do it

Explanation:

Suppose the pickpocket is caught at a time t after motorcycle starts. The distance traveled by the motorcycle during this interval is

s= 21

at 2

...(1)

During this interval the jeep travels a distance

s + d = vt ...(2)

By (1) and (2),

21

at 2 +d=vt

or,

t= av± v 2 −2ad

The pickpocket will be caught if t is real and positive.

This will be possible if

v 2

≥2ador,v≥ 2ad

Hence, the pick pocket will be caught if v

2 ≥2ador,v≥ 2ad