Physics, asked by amithkamal2007, 5 hours ago

Reaction time of a driver is the time interval between the moment the driver sights an obstacle and the moment he applies the brakes. During this time the car travels with a constant speed at which he is driving and gets nearer to the obstacle. A driver has a reaction time of 0.5 s and is travelling at 72 kmph on a straight road. What should be the minimum deceleration produced by the brakes of his car if he should avoid hitting an obstacle 50 m away from the car at the moment he sees it.
A) 5m/s C) 3m/s D) 2ms​

Answers

Answered by pya120883
3

Answer:

5m/s

this is the correct answer of this question

Answered by Se4ted
4

Answer:

5ms^-2

Explanation:

Given,

Reaction time = 0.5s

u ( initial velocity) = 75kmph = (75*5/18)m/s = 20m/s

v (Final Velocity) = 0m/s

S (displacement) = 50 m

Distance travelled before the driver started to apply brakes

=> V = S/T

=> S = VT

=> S = 20*0.5

       = 10m

So, Distance travelled before stop, 50-10 = 40m

now apply to 3rd equation of motion

=> v2 - u2 = 2as

0 - (20)^2 = 2.a.40

=> -400/80 = a

a = 5ms^-2

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