I'm doing some problems I found here:(adsbygoogle = window.adsbygoogle || []).push({});

http://library.thinkquest.org/10796/ch4/ch4q.htm

A car is moving at a constant velocity of 20 km/h (5.56 m/s). How much net force is required to raise its velocity to 50 km/h (13.89 m/s) in 30 seconds? Suppose the car has a mass of 150 kg.

I used F= (150kg)([13.89m/s-5.56m/s]/30s)

and got 41.65 N but apparently that's wrong. What am I doing wrong?

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# Net force and acceleration

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