Question

For a body, angular velocity `vecomega= hati-2hatj+3hatk` and radius vector `vecr=hati+hatj+hatk`, then its velocity `(vecv= vecomega xx vecr)` is :
A. `-5hati+2hatj+3 hatk`
B. `-5hati+2hatj-3 hatk`
C. `-5hati-2hatj+3 hatk`
D. `-5hati-2hatj-3 hatk`

Answer 1

Correct Answer - A
`vecv=vecwxxvecr`
`|{:(hati , hatj , hatr), (1 , -2 , 3), (1 , 1, 1):}|`
`=hati(-2-3)-hatj(1-3)+hatk(1+2)`
`=-5hati+2hatj+3hatk`