बिन्दु (2, 0, - 3) पर कार्यरत् बल `vecF = 4hati+5hatj-6hatk` का बिन्दु (2,-2,-2) के परितः आघूर्ण होगा |

Options

A. `-7hati -8hatj - 4hatk`
B. `-4hati - hatj - 8hatk`
C. `-8hati-4hatj - 7hatk`
D. `-7hati - 4hatj - 8hatk`

Answer

D

Explanation

बल आघूर्ण `vec tau = vec r xx vec F`
`vecr = (2hati + 0 hatj - 3hatk) - (2hati - 2hatj - 2hatk) " या " vecr = 0hati + 2hatj - jatk " तथा " vec F = (4hati + 5hatj - 6hatk)`
`vecrtau = vecr xx vecF = |{:(hati , hatj , hatk), (0 , 2 , "-1"), (4 , 5 , "-6"):}| " या " vec tau = (-12 + 5) hat i - (0 +4)hatj +(0-8)hatk " या " vec tau = -7 hat i - 4hatj - 8hatk`