Thought experiment: we claim that the air track is frictionless, but this is not entirely true. how would our newton's 2nd law models (eq. 1 and eq. 3) of the two systems studied in this lab change if we were to account for the force of friction acting on the glider as it travels across the track? draw force diagrams to you. use f to denote the mathematical term for the force of friction. ww hence a fixed force (f = mhg). mass will be added to the glider, so that: f=mng = (m + mn)a (eq. 1) resulting in: fmg sin 0= ma (eq. 3)