Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

Embarassed to ask as seems simple, i have done the maths but answer seems too low! - have looked all over for worked example to follow but no luck :(

I have a free rolling mass of 2200kg that is being driven down a slope at 0.204m/s.

This mass must be braked to a stop in 0.5m i need to calculate the brake force required to do this.

I have calculated mg sin8.5° = 3190N

v2=u2+2as => 0 = 0.041616 + 2a x 0.5m

a = 2 x -0.041616 /0.5 => cancels out to give 0.041616m/s/s

F=ma so 2200 x 0.041616 = 91.55N

Add together gives 3281.555N

Reason i'm scared is that the force to decelerate (91.55N) seems so small but reletive to the speed 0.5m is quite a long distance i suppose!!

Can anyone confirm my reasoning please!!

Thanks!

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# Homework Help: Deceleration of a mass down hill

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