Question

In unit-vector notation, what is the net torque about the origin on a flea located at coordinates (-2.0, 4.0 m, -1.0 m) when forces F1 = (-4.0 N) k and F2 = (-5.0 N) j act on the flea?

Answer 1

Torque,
`\tau=-21i-8j+10k`

Step-by-step explanation:

Given that,

Coordinates,
`r=(-2i+4j-k)\ m`

Force acting on the flea,
`F=(0i-5j-4k)\ N`

Let
`\tau` is the net torque about the origin on a flea. It is given by the following formula :

`\tau=r* F`

`\tau=(-2i+4j-k)* (0i-5j-4k)`

`\tau=\begin{pmatrix}-21&-8&10\end{pmatrix}`

`\tau=-21i-8j+10k`

So, the net torque about the origin on a flea is
`-21i-8j+10k`. Hence, this is the required solution.