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3 years ago

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A car is traveling north at 17.7m/s After 12 s its velocity is 14.1m/s in the same direction. Find the magnitude and direction o

f the car's average acceleration.A2.7 m/s2, north b0.30 m/s2, south c2.7 m/s2, south d0.30 m/s2, north

1 answer:

dem82 [27]3 years ago

7 0

Answer:

Option B

0.3 m/s2 South

Explanation:

Acceleration, $a=\frac {v-u}{t}$ where v and u are final and initial velocities respectively, t is the time taken

Substituting 14.1 m/s for v, 17.7 m/s for u and 12 s for t then

$a=\frac {14.1 m/s- 17.7 m/s}{12}=-0.3 m/s^{2}$

Since this is negative acceleration, it's direction is opposite hence 0.3 m/s2 South

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