The vector sum of two forces is perpendicular to their vector difference. In that case, the forces :

Options

A. are equal to each other in magnitude
B. are not equal to each other in magnitude
C. cannot be predicted
D. are equal to each other

Answer

C

Explanation

(a): As given condition

`(vecA+vecB).(vecA-vecB)=|vecA|^(2)-|vecB|^(2)`
`0=A^(2)-B^(2)`
(Dot product is zero for perpendicular vectors)
`rArr A=B`