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A thief in stolen car passes through a p...

A thief in stolen car passes through a police check post at his top speed of `90kmh^(-1)`. A motorcycle cop, reacting after 2s, accelerates from rest at `5ms^(-2)` His top speed being 108km/h. Find the maximum separation between policemenk and thief

A

112.5m

B

115m

C

116.5m

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
A
At maximum speration their velocities are same
`:.` Velocity of car =25 m/s [90 km/hr=25m/s]
or `at=25` or `t=5s" " :. a=5ms^(-2)`
But thief has travelled up to 7s
`s_(1)=` displacement of thief `=v_(1)t_(1)=25xx7=175m`
`s_(2)=` displacement of motorcycle `=1/2xxa_(2)t_(2)^(2)=1/2xx5xx(5)^(2)=62.5m`
`:.` Maximum separation `=s_(1)-s_(2)=112.5m`
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