Question

A car is running at the rate of 54 km per hour suddenly the driver applies brakes and stops the car within a distance of 7.5 M what is the acceleration produced by the brakes assume that the acceleration is uniform one please answer fast its urgent

Answer 1

Howdy!!

your answer is ----

Given,

initial velocity u = 54km/h or 15m/s

distance s = 7.5meter

driver applied break after 7.5 meter

so, final velocity v = 0

Let , acceleration be a

now, according to formula

${v}^{2} = {u}^{2} + 2as \\ = > 0 = {15}^{2} + 2 \times a \times 7.5 \\ = > 0 = 225 + 15a \\ = > 15a = - 225 \\ = > a = - \frac{225}{15} = - 15m {s}^{ - 2}$

hence, acceleration is -15m/s^2 . negative sign show that car deaccelerate .

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hope it help you

Answer 2

Explanation:

initial velocity u = 54km/h or 15m/s

distance s = 7.5meter

driver applied break after 7.5 meter

so, final velocity v = 0

Let , acceleration be a

v²=u²+2as

0=15²+2×a×7.5

0=225+15a

15a= -225

a= -225/15

-15m/s

Hope it is help full

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