A 1000 kg car travelling rightward at 25 m/s slams on the breaks and skids to a stop (with locked wheels). Find the distance required to stop it. Coefficient of friction between the tires and the road is 0.95. Let g=9.8 m/s^2(adsbygoogle = window.adsbygoogle || []).push({});

Solution:

2aΔx=vf2- vo2

a=µg

2 µg Δx=vf2- vo2

vf=0

2 µg Δx=- vo2

Δx=- vo2/2 µg

Δx=-252/(2×0.95×9.8)

Δx=-33.6 m

The answer became -33.6 m. Why is the value negative? The correct answer is 33.6. Thank you in advance!

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# Homework Help: Negative value when calculating the distance

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