Question

when a car travel at a speed of 60km/he applies brake it comes to rest in 15s then the retardation of the car is​

Answer 1

Initial velocity of the car (u) = $60km/hr^2$ = $16.67 m/s^2$

Final velocity (v) = 0 m/s

Time = 15s

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Use this equation

v = u + at

0 = 16.67 + a(15)

15 a = -16.67

15 will shift

Divide it

a = $- 1.12 m/s^2$

The retardation of the car = $- 1.12 m/s^2$

Answer 2

ANSWER:-

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Given:-

• Intial velocity of the car (u) = $\bf{60km/hr}$

$\bf{\implies{16.67 m/s^2}}$

Final velocity (v) = $\bf{0 m/s}$

Time = $\bf{15s}$

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• SOLUTION:-

We know:-

$\boxed{\bf{v = u + at}}$

• Putting the values:-

0 = 16.67 + a[15]

0 = 16.67 + 15a

15 a = -16.67

$a = {\bf{\frac{-16.67}{15}}}$

$a = - 1.11133 m/s^2$

$\implies{\bf{-1.12 \: m/s^2}}$

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Therefore, the Retardation of the car is:

$\bf{- 1.12 m/s^2}$

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