Find the torque about the origin when a force of `3 hatj` N acts on a particle whose position vector is `2 hatk` m

Options

A. `5 hatj Nm`
B. `-6 hati Nm`
C. `6 hatk Nm`
D. `6 hati Nm`

Explanation

`bar F = 3 hatj N, bar r = 2hatk`
`bar tau = bar r xx bar F = 2 hatk `
`=6 ( - hati)`
`bar tau = - 6 hati Nm`