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A car accelerates at 2.0 m/sec​2​ for a distance of 15.0 m, starting from rest.

(a) What was the time of this travel?
(b) What was the final velocity?

User Abu Shumon
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1 Answer

7 votes

Final answer:

The car travels a distance of 345.6 meters in 12.0 seconds and its final velocity is 28.8 m/s.

Step-by-step explanation:

The car accelerates from rest at a rate of 2.40 m/s² for 12.0 seconds, so we can use the equations of motion to find the unknowns in this problem.

(a) Draw a sketch of the situation:

While entering a freeway, the car starts from rest and accelerates.

(b) List the knowns in this problem:

Initial velocity (vi) = 0 m/s (starting from rest)

Acceleration (a) = 2.40 m/s²

Time (t) = 12.0 s

(c) How far does the car travel in those 12.0 seconds?

To find the distance traveled (d), we can use the kinematic equation:

d = vit + 0.5at²

Plugging in the given values:

d = (0 m/s)(12.0 s) + 0.5(2.40 m/s²)(12.0 s)²

d = 0 + 0.5(2.40 m/s²)(144.0 s²)

d = 0 + 345.6 m

d = 345.6 m

Therefore, the car travels a distance of 345.6 meters in those 12.0 seconds.

(d) What is the car's final velocity?

To find the final velocity (vf), we can use another kinematic equation:

vf = vi + at

Plugging in the given values:

vf = 0 m/s + (2.40 m/s²)(12.0 s)

vf = 0 m/s + 28.8 m/s

vf = 28.8 m/s

Therefore, the car's final velocity is 28.8 m/s.

User Surftijmen
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