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3 years ago

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While Calvin is doing a physics experiment outside with a radar gun, he notices that after three seconds a car reaches a speed o

f 20 m/s while accelerating at 3 m/s squared. what was the initial velocity of the car?

1 answer:

nirvana33 [79]3 years ago

3 0

The initial velocity of the car is 11 m/s.

Explanation:

Here, we can use the equations of motions.
The first of equation of motion is v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time.

The given parameters are,

Final velocity, v = 20 m/s

acceleration of the care, a = 2 m/ $s^{2}$

time, t = 3 s

Initial velocity, u = ?

Hence, the equation can be written as u = v - at

once you substitute all these vales, you will get u = 11 m/s

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