A student stands on a uniform 25 kg beam. The scale on the right reads 350 N. What is the mass of the student? Answer is 58Kg. I dont understand what is the deal with the scale? I think I figured this out but I'm not sure. The force of the scale is opposite the force of the beam, girl right? If so why? Isn't the force on the centre of rotation equal to the force on the scale?