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3 years ago

13

The driver of a car traveling 110 km/h slams on the brakes so that the car undergoes a constant acceleration, skidding to a comp

lete stop in 4.5 sec. What is the average acceleration of the car during braking?

1 answer:

Ber [7]3 years ago

5 0

Answer: $-6.80\ ms^{-2}$

Explanation:

We know that the formula for acceleration is given by:

$a=\dfrac{v-u}{t}$ , where v = Final velocity

u= Initial velocity

Given : The driver of a car traveling 110 km/h slams on the brakes so that the car undergoes a constant acceleration.

i.e. u= 110 km/h $=\dfrac{110\times1000}{3600}\approx35.6\ m/s$ [∵ 1 km= 100 meters and 1 hour = 3600 seconds]

v= 0 m/s ( At brake , final velocity becomes 0)

t=4.5 seconds

Substitute all the values in the formula , we get

$a=\dfrac{0-30.56}{4.5}\approx-6.80\ ms^{-2}$

Hence, the average acceleration of the car during braking is $-6.80\ ms^{-2}$ .

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Put this value in the equation (1).

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