# Tricky Problem (at least for me)

1. May 12, 2006

### need help

If I have a initial velocity of 0m/s and an acceleration of .76m/s2 and a distance of 2meters what would my final velocity be?

Also I need to find F(net) I know a mu of .15 a time of 5seconds a mass of 5kg and force of gravity equals 49N an normal force equals -49N and force of friction equals -7.35N. I think I'm supposed to use the velocity found in the question above, but I'm not sure and I don't know how. How do I find F(net) with the information I have and what is the answer??

Any help would be greatly appriciated...

2. May 12, 2006

### nrqed

$v_{f,x}^2 = v_{i,x}^2 + 2 a_x (x_f-x_i)$ where x_f-x_i is essentially the distance traveled. have you seen this equation before?
It

The key point is that the magnitude of the friction force is equal to the magnitude of the normal force times the coefficient of kinetic friction $\mu_k$