Task. Resolve the force if 100N acting at an angle of 39∘ with the horizontal in 2 vertical and horizontal components.
Solution. We assume that the vector F of the force lays in the plane (x,y) so that the x -axis is horizontal and y -axis is vertical. Let F=(Fx,Fy) be the coordinates of its vector. We should find Fx and Fy .
By assumption the length of this vector ∣F∣=100N , and the angle with x -axis is 39∘ . Therefore,
Fx=∣F∣cos39∘=100∗0.77715=77.715N,
and
Fy=∣F∣sin39∘=100∗0.62932=62.932N.
Answer. Fx=77.715 N , Fy=62.932 N .