If the magnitude of sum of two vectors is equal to the magnitude of difference of the two vectors, the angle between these vectors is
(a)90° (b)45° (c) 180° (d) 0°
Concept Videos :-
Concept Questions :-
(a) Suppose two vectors are P and Q. It is given that [P+Q]=[P-Q]
Let angle between P and Q is φ.
∴ P2+Q2+2PQ cosφ=P2+Q2-2PQcosφ
=> cosφ=0 [∴ P,Q≠0]