Force of gravity = fg = always in the direction of the center of the earth
force applied = fa = the force applied to an object by an outside force
force of friction = ff = always opposes the motion of an object
force in a spring = fs = a compressed spring will push, a stretched spring will pull
normal force = fn = when an object sits on a surface, that surface pushes back. the
normal force is always perpendicular to the surface of support.
regarding the book. what is the actual value of both fn and fg in this
case?
o newtons
45 newtons
90 newtons