Question

The resultant of two forces acting at a point at right angles to each other is 40 pounds. If the horizontal force is 30 pounds what angle does the 30 lb. force make with the resultant

Answer 1

In the right triangle, the hypotenuse is 40 (pounds) and the adjacent side is 30, suggesting the use of the cosine ratio.

$\cos{\theta}=\frac{30}{40} = .75$

Use the inverse cosine function to find theta.

$\cos^{-1}{.75} \approx 41.4^\circ$