Question

magnitude of sum of two vectors of equal magnitude is equal to magnitude of given vectors then angle between them is​

Answer 1

THIS IS YOUR ANSWER

Let the two vectors be

A

and

B

with magnitudes A and B respectively. Then magnitude of their sum is given by:

∣

A+ B= A 2+B 2+2ABcosθ

→(1) (θ= angle between the vectors)

Magnitude of their difference is given by:

A− B= A 2+B 2−2ABcosθ

→(2)As ∣ A+ B ∣=∣ A− B∣

⇒A 2+B 2+2ABcosθ=A2+B 2−2ABcosθ

⇒4ABcosθ=0 or cosθ=0

⇒θ=90

o

.