Four co-planar forces of magnitudes 10N, 17N, 6N and 20N act at point O as shown in the above diagram. Determine the magnitude of the resultant force?

A. 53.N
B. 21.0N
C. 7.0N
D. 5.0N

Correct Answer: Option D

D. 5.0N

Explanation

Vertical resultant = 10 – 6 = 4N

Horizontal resultant = 20 – 17 = 3N

R = √3²+4²

= 5N