The sum of two forces P → and Q → is R → such that R → = P → . Find the angle between resultant of 2 P → and Q → and Q → , ________

Step-by-step solution

So angle between 2 P → + Q → and Q → is 90 o Alternate solution P → + Q → = P → P 2 + Q 2 + 2 P Q cos ⁡ θ = P 2 ⇒ Q + 2 P Q cos ⁡ θ = O ⇒ cos ⁡ θ = - Q 2 P tan ⁡ α = 2 P sin ⁡ θ 2 P cos ⁡ θ + Q = ∞ ∵ 2 P cos ⁡ θ + Q = 0 α = 90 o