7. Four perpendicular forces, 2 N, 3 N, 9 N and 10 N act on object P as shown in Diagram 2. 10 N A B 9 N 3 N 2 N P Diagram 2 What is the magnitude of the resultant force? 10 N C 18 N 14 N D 20 N

Answer: R=
A
2
+B
2
+2ABcosθ
θ=90
o
cos90
o
=0
R=
A
2
+B
2
=
3N
2
+4N
2
=5N
Explanation: