Question

If F1 = 390 N and F2 = 550 N , determine the angle θ(0∘≤θ≤180∘) between them, so that the resultant force has a magnitude of FR = 780 N .Express your answer to two significant figures and include the appropriate units.

Answer 1

Answer:

Explanation:

R² = F₁² + F₂² + 2F₁F₂ Cosθ , R is resultant force , θ is angle between them

780² = 390² + 550² + 2 x 390 x 550 Cosθ

608400 = 152100 + 302500 + 429000  Cosθ

Cosθ =  .3585

θ  = 69 degree.