Question

)A car moving with a speed of 126 km/h is brought to a stop within a

distance of 200 m. Calculate the retardation of the car and the time

required to stop it.
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Answer 1

$\huge \mathbb{ \underbrace{\red{Question\:}}}$

A car moving with a speed of 126 km/h is brought to a stop within a distance of 200 m. Calculate the retardation of the car and the time required to stop it.

$\huge{\boxed{\sf Answer}}$

a = -30.625 ; t = 1.1428 sec

Given:-

u = 126km/h ; v = 0 ; s = 200m

Formulas:-

• v² - u² = 2as
• v = u + at
• s = ut + 1/2 at²

$\huge{\boxed{\sf Solution}}$

0² - 35² = 2(a)(200)

1225 = 400a

a = 1225/400

a = -30.625

v = u + at

0 = 35 + (-30.625)t

-35 = -30.625t

t = -35/-30.625

t = 1.1428 sec