the sum of three forces f1=100n, f2=80n, f3=60n acting on a particle is zero.
The angle between f1 and f2 is:
science(physics) - drwls, Friday, June 10, 2011 at 10:22am
you don't say what n is, but it looks like all three vectors are in the same direction. It would not be possible for the sum of all three to be zero, since they are all positive