(adsbygoogle = window.adsbygoogle || []).push({}); Unsolvable? Kinematics - Constant deceleration and friction

Here's the way the problem is laid out:

A car travels at 52.4 km/hr on a flat highway. If the coefficient of kinetic friction is 0.151, what is the minimum distance needed for the car to stop?

Given:

V_{i}= 52.4 km/hr (calculated as 14.555(...) m/s)

V_{f}= 0 m/s

mu_{k}= 0.151

g = 9.81 m/s^{2}

Unknown:

/\ x, /\ t, a,m

It seems to me that I have too many missing variables to solve the problem.

I know that V_{avg}= (V_{i}+ V_{f})/2, so the average velocity would be around 7. 277 m/s, but without /\t, I can't carry out any of the normal kinematic equations to find /\x, and withoutm, I can't figure out F_{k}, F_{g}, or F_{N}.

Is there something I'm missing, or is the problem actually unsolvable?

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# Homework Help: Kinematics - Constant acceleration and friction

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