Answer:
Torque, [tex]\tau=-21i-8j+10k[/tex]
Explanation:
Given that,
Coordinates, [tex]r=(-2i+4j-k)\ m[/tex]
Force acting on the flea, [tex]F=(0i-5j-4k)\ N[/tex]
Let [tex]\tau[/tex] is the net torque about the origin on a flea. It is given by the following formula :
[tex]\tau=r\times F[/tex]
[tex]\tau=(-2i+4j-k)\times (0i-5j-4k)[/tex]
[tex]\tau=\begin{pmatrix}-21&-8&10\end{pmatrix}[/tex]
[tex]\tau=-21i-8j+10k[/tex]
So, the net torque about the origin on a flea is [tex]-21i-8j+10k[/tex]. Hence, this is the required solution.
