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cowgiljl
Dec13-03, 11:54 AM
A truck weighs 6000 lb. The truck is going around a curvewith a radius of 650 feet. The maximum friction force the road can exert on the tires is 1125 lb. it wants me to calculate the velocity in ft/sec

I am sorta lost on this an y help would be great

thanks

gnome
Dec13-03, 12:01 PM
Think about centripetal acceleration & centripetal force.

What is needed to keep the truck moving along that curve, and what can the road provide?

cowgiljl
Dec14-03, 12:07 AM
right now the only thing I know what to do is I converted the items that are in pounds to Kg. and feet to m

struggling

deltabourne
Dec14-03, 12:28 AM
OK, centripetal acceleration is given by v^2/r.

And by Newton's second law, we know that F=ma. Since the car is moving in a circular path, he is accelerating. The only force that is pointing towards the center of the circle is friction. So:
F=ma
Force of friction = m*(v^2/r)
1125lb = 6000lb*(v^2/650ft)
v=11.039701082909808568455053408699 ft/s

cowgiljl
Dec14-03, 08:28 AM
thanks alot i have been trying to catch up on all the homewok and study for my physics final

thanks again