Question

Example 8.7 The brakes applied to a car
produce an acceleration of 6 m s2 in
the opposite direction to the motion. If
the car takes 2 s to stop after the
application of brakes, calculate the
distance it travels during this time.
​

Answer 1

$\huge{\mathfrak{Answer:-}}$

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a = -6 ms^-2

(negative because brakes are applied)

t = 2s

v = 0

( after brakes are applied , cars come to a rest. Hence, final velocity (v) = 0)

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To Find:-

Distance (s)

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First we will have to find the intial velocity

As we know,

v = u + at

0 = u + -6×2

0 = u - 12

12 = u

Hence, the intial velocity (u) is 12 m/s

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Now, we will use the formula

v²-u² = 2as

Hence, we get

0² - 12² = 2×-6×s

-144 = -12s

s = 12m

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Hence

$\boxed{Distance\:Travelled=12m}$