posted by Fiyin .
a constant force equal to (5i+2j)N moves a particle through a displacement S=(2i+3j). Calculate the workdone by the force. At what angle to the horizontal was the force applied?
The work done is the dot product of force and displacement vectors, which is
5*2 + 3*2 = 16 Joules
If the j component is up and the i component is horizontal, the force angle from the horizontal is arctan(2/5) = 21.8 degrees.