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Illusion [34]
3 years ago
12

A motorcycle is moving at a speed of 21 m/s. The driver applies the brakes, giving hum an acceleration of -2.4 m/s^2. After 2 se

conds of braking, what is the speed of the motorcycle?
A. 25.8 m/s
B. 16.2 m/s
C. 4.8 m/s
D. 2.4 m/s
Physics
1 answer:
WARRIOR [948]3 years ago
6 0
<h3><u>Answer;</u></h3>

B. 16.2 m/s

<h3><u>Explanation</u>;</h3>

Using the equation;

v = u + at; where v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken;

u = 21 m/s, a= -2.4 m/s^2 and t = 2 seconds

Therefore;

v = 21 + ((-2.4) × 2)

  = 21 - 4.8

 <u> = 16.2 m/s</u>

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