Hi, For a school project I have created a system which applies an equal force to 4 objects of measurable friction. Each yields a frictional force of approx. 3N (calculated from F = μFNormal) when in motion - but I am not quite sure as to calculating the total frictional force the combined set of 4 generates 'together' against the system supplying the same applied force across all of them. Is it as simple as adding the 4 frictional forces together? Or perhaps more complex, through employing the parallel equation of (1/FTotal) = (1/F) + (1/F) + (1/F) + (1/F), for example? Or maybe its something different? Thanks in advance for any help.