Question

Determine whether the forces in the pair are pulling at right angles to each other.

For each group of three forces below, determine whether the forces in each pair are pulling at right angles to each other.

13 lb, 35 lb, resultant force 30 lb no; 20 lb, 15 lb, resultant force 25 lb yes
13 lb, 35 lb, resultant force 30 lb no; 20 lb, 15 lb, resultant force 25 lb no
13 lb, 35 lb, resultant force 30 lb yes; 20 lb, 15 lb, resultant force 25 lb no
13 lb, 35 lb, resultant force 30 lb yes; 20 lb, 15 lb, resultant force 25 lb yes