Given that `vecA+vecB+vecC=0`, out of three vectors two are equal in magnitude and the magnitude of third vector is `sqrt2` times that of either of two having equal magnitude. Then angle between vectors are given by

Options

A. `30^@`,`60^@`,`90^@`
B. `40^@`,`45^@`,90^@`
C. `45^@`,`60^@`,`90^@`
D. `90^@`,`135^@`,`135^@`

Answer

D

Explanation

From polygonlaw, three vectors having summation zero should form a closed polygon (triangle) since the two vectors are having same magnitude and the third vector is `sqrt(2)` times that of either of two having equal magnitude, That is the triangle should be right angled triangle.
Angle between A and B, `alpha90^@`
Angle between B and C, `beta=135^@`
Angle between A and C, `gamma=135^@`.