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A driver takes 0.20 s to apply the brake...

A driver takes 0.20 s to apply the brakes after he sees a need for it. This is called the reaction time of the driver. If he ils driving a car at a speed of 54 km/h and the brakes cause a deceleration of `6.0 m/s^2`, find the distance travelled by the car after he sees the need to put the brakes on.

Text Solution

Verified by Experts

(distance covered during 0.20 s) + (distance covered until rest)
`=(15xx0.25)+[18.75]=21.75m`
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Knowledge Check

  • A driver applies the brakes on seeing traffic singal 400m ahead. At the time of applying of brakes vehicle was moving with speed 15 m//s . The brekes provide uniform deceleration of 0.3m//s^(2) . The displacement of the vehicle in 1 mmin duration after the driver sees the singal is :

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    B
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    C
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    D
    `40m`

  • A person driving a car with a speed 72 km/h suddenly sees a boy crossing the road. If the distance moved by car, before the person applies brakes is 5 m, the reaction time of the person is

    A
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    B
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    C
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  • The distance travelled by a motor car in t seconds after the brakes are applied is s feet where s=22t-12t^(2) . The distance travelled by the car before it stops, is

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