A force `F=(2hati+3hatj-hatk)N` is acting on a body at a position `r=( – InterviewSolution

InterviewSolution

1.	A force `F=(2hati+3hatj-hatk)N` is acting on a body at a position `r=(6hati-3hatj-2hatk)`. Calculate the torque about the originA. `(3hati+2hatj+12hatk)Nm`B. `(9hati+2hatj+7hatk)Nm`C. `(hati+2hatj+12hatk)Nm`D. `(3hati+12hatj+hatk)Nm`
Answer» (a) `tau=rxxF=\|(hati, hatj, hatk),(6,3,-2),(2,3,-1)\|` `=hati(-3+6)-hatj(-6+4)_hatk(18-6)` `=tau=(3hati+2hatj+12hatk)Nm`

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