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A car is moving with speed u. Driver of ...

A car is moving with speed u. Driver of the car sees red traffic light. His reaction time is t, then find out the distance travelled by the car after the instant when the driver decided to apply brakes. Assume uniform retardation 'a' after applying brakes.

Text Solution

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During the reaction time, the car will move with constant speed.
So, `S_1 =ut`
The distance covered by the car after brakes are applied `S_2 = (0^(2) - u^(2))/(-2a)= (u^(2))/(2a) `
So Total distance travelled = `S_1 + S_2 = ut + (u^(2))/(2a)`
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