So I've always had problems figuring out what exactly the lever arm is in figuring out a torque problem, in which

Torque=(Force applied)x(Lever Arm)

According to definition I found online, lever arm is "the perpendicular distance from the axis of rotation to the line of action of the force." But this definition does not really makes sense to me. So I tried to figure out what lever arm is in my own method, which I've attached.

So, basically what I did was I draw a straight line through the axis of rotation so it will be parallel to the force(indicated by green line), and the lever arm is the shortest distance between those two parallel lines(indicated by pink line).

So my question is, is this one of the correct ways to determine the lever arm?

Torque=(Force applied)x(Lever Arm)

According to definition I found online, lever arm is "the perpendicular distance from the axis of rotation to the line of action of the force." But this definition does not really makes sense to me. So I tried to figure out what lever arm is in my own method, which I've attached.

So, basically what I did was I draw a straight line through the axis of rotation so it will be parallel to the force(indicated by green line), and the lever arm is the shortest distance between those two parallel lines(indicated by pink line).

So my question is, is this one of the correct ways to determine the lever arm?