## Fundamentals of Physics Extended (10th Edition)

$-63.4^{\circ}$
To find the angle that the vector Fnet = 1N i + -2Nj makes with the x axis, we need to use trigonometry. We start at the origin and make a right triangle with a base of 1 unit (because of the 1N i) and a height of 2N (because of the -2N j) and then we find the angle. To do this we use the fact that $tan(\theta) = opposite/adjacent = y/x$ therefore $tan(\theta) = 2/1$ and therefore $\theta = 63.4^{\circ}$. However, since the x is positive and the y is negative, we are in quadrant IV, therefore the angle we make with the x axis is negative so the answer is -63.4