# Newton's Second Law of Motion (problems)

by love_joyously
Tags: motion, newton
 P: 395 1) First $$F = ma$$, also you know the distance and time and that it started from rest, you can find the acceleration easily using $$d=\frac{at^2}{2}$$. 2) I am guessing you are having problems finding the acceleration. The acceleration is uniform here, so use $$d=\frac{v_1-v_0}{2}t$$ to find the time it takes to travel ($$v_0$$ and $$v_1$$ are the inital and final velocities respectively) and then using that time $$d=\frac{at^2}{2}+v_0t$$. I hope this helps. Do not be discouraged when you cannot solve these, I almost failed physics my freshman year.
 P: 787 Newton's Second Law of Motion (problems) In order to calculate the net force, you need the mass (given) and the acceleration. You will also indicate a direction of the force for this problem, as force is a vector quantity. So, we all know $$F_{net} = ma$$ You have the mass, so let's solve for the acceleration. Use one of those nice kinematic equations... I'll pick one. $$v_{f}^2 = v_{i}^2 + 2ad$$ You know everything but "a", so use those algebra skills and solve for it.