Answer:
[tex]\tau = L F_y \hat i [/tex]
Explanation:
As we know that torque due to applied force is given as
[tex]\tau = \vec r \times \vec F[/tex]
here we know that
[tex]\vec r = -L\hat k[/tex]
applied force is given as
[tex]\vec F = F_y \hat j + F_z \hat k[/tex]
now we will have
[tex]\tau = (-L \hat k) \times (F_y \hat j + F_z \hat k)[/tex]
[tex]\tau = L F_y \hat i [/tex]