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a car traveling at 28 m/s slows down at a constant rate for 4 seconds until it stops. what is its acceleration?

User JamesR
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1 Answer

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We are given the following conditions:

v_(0) = 28m/s t = 4s v_(f) = 0m/s

Since we are told it slows down at a constant rate, we know we are dealing with uniformed accelerated motion, or UAM for short.

So we look at our kinematics equation that contains the given variables.


v_f = v_0 + at

This contains our target variable and our initial conditions. Plug and chug, we get:


(0m/s) = (28m/s) + a(4s) -28m/s = (4s)*a a = -7m/s^2

Thus the answer is:

a = -7m/s^2

Hope this helps!


User Gustavo Bissolli
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