//when a new pulley is added
public void AddNewMoveablePulley()
{
pulley_mass.AddPulleyToMass(); //add a support pulley to the mass
//when a moveable pulley is added there is no longer a SupportRope
pulley_mass.RemoveSupportRope();
PulleyController.AddMoveablePulleyToScene();
PulleyController.GetPulleysInScene(); //add all the pulleys back to the list of pulleys
PulleyController.CalculateMechanicalAdvantage();
num_moveable_pulleys++;
}
