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A car traveling at a constant acceleration covers the distance between two points 180m apart in 6 seconds if the speed of the car at the second point is 45 m/s what is the acceleration of the car?

User Alexriedl
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1 Answer

2 votes

Answer:
15 m/s^(2)

Step-by-step explanation:

We have the following data:


d=180 m is the distance traveled by the car


t= 6 s is the time of travel


u=45 m/s is the car's final velocity


v is the unknown car's initial velocity


a is the car's constant acceleration

Now, we can solve this problem with the following equations of motion:


u=v+at (1)


d=vt+(1)/(2)at^(2) (2)

Isolating
v from (1):


v=u-at (3)


v=45 m/s-(6 s)a (4)

Substituting (4) in (2):


d=(45 m/s-(6 s)a)t+(1)/(2)at^(2) (5)

Solving and finding
a:


180 m=(45 m/s)(6 s)-36 s^(2)a+(1)/(2)a(6 s)^(2) (6)

Finally:


a=15 m/s^(2) This is the car's acceleration

User Adam Kinney
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5.4k points