Let `vec(A)=hat(i)A cos theta+hat(j)A sin theta`, be any vector. Another vector `vec(B)` which is normal to `vec(A)` is :-

Options

A. `hati B costheta -hatj B sin theta `
B. `hati B sin theta -hatj B cos theta `
C. `hati B sin theta+hatj B cos theta `
D. `hati B sin theta+hatj B cos theta `

Answer

B

Explanation

(b) Dot product of two perpendicular vector should be zero .
`thereforeB=hatiBsintheta-hatjBcostheta`
`[:'(hatiAsintheta)(hatiBsin theta-hatjBcostheta)=0]`