Tnet = F x r = (40N + 30N) x .03m
but something is wrong here.......i don't know wht
You're on the right lines, but you need to be careful here.
What is the definition of F and r?
F is the force and r is the radius
It is the position vector directed from the centre of rotation to the line of action of the force. Another important point to realise is that you need to take the cross product of F and r, not simply multiply them.
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