he drawing shows a lower leg being exercised. It has a F = 48 N weight attached to the foot and is extended at

Question

he drawing shows a lower leg being exercised. It has a F = 48 N weight attached to the foot and is extended at an angle with respect to the vertical. Consider a rotational axis at the knee.
At what angle does the magnitude of the torque equal 13 Nm?

Answer 1

And the drawing is...


To determine the torque we need force (F) and an arm (R)

T=R x F
or
T=|R| |F| sin(angle between R and F)

angle = arcSin(T/(|R| |F| )) So what is R?