If the magnitude of sum of two vectors is equal to the magnitude of difference of the two vector, the angle between these Vector is

Options

A. `90^(@)`
B. `45^(@)`
C. `108^(@)`
D. `0^(@)`

Answer

a

Explanation

Suppose two vectors are P and Q
It is given that
`|P+Q|=|P-Q|`
Let angle between P and Q is `phi`
`:.P^(2)+Q^(2)+2PQcosphi=P^(2)+Q^(@0-2PQcosphi`
`implies4PQcosphi=0`
`impliescos phi=0" " (: .P,Q cancle(=))`
`implies" "phi=(pi)/(2)=90^@)`