Posted by Kyle on Tuesday, October 4, 2011 at 2:29am.
You find it takes 230 N of horizontal force to move an unloaded pickup truck along a level road at a speed of 2.4 m/s. You then load up the pickup and pump up its tires so that its total weight increases by 42% while the coefficient of rolling friction decreases by 19%.
Now what horizontal force will you need to move the pickup along the same road at the same speed? The speed is low enough that you can ignore air resistance.
Would I have to find the coefficient for the rolling friction for this problem? I'm really not sure how to start it.

Physics  Henry, Wednesday, October 5, 2011 at 4:44pm
Increasing the load by 42% caused the
force of friction to increase by 42%.But the addition of air to the tires caused a 19% decrease in force of
friction:
F = (100%+42%19%)*Fo,
Change % to decimal:
F = (1+0.420.19)*230 = 283N.