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The driver of a car travelling at 72 km ...

The driver of a car travelling at `72 km h^(-1)` suddenly sees a big rock on the road at a distance of 20m. What can he do to avoid a collision ?

A

Apply brakes

B

Turn sharply

C

Follow a zig - zag path

D

Shut the engine

Text Solution

Verified by Experts

The correct Answer is:
A
The required retardation is given by
`a=(v^(2))/(2x)=(20xx20)/(2xx20)=10 ms^(-2)`
The centripetal acceeration required to describe a circle of radius 20 mis
`(v^(2))/(R)=(20xx20)/(20)=20 ms^(-2)`
Thus, it better to apply the brakes
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