LEBZA

60.0 kg boy and a 40.0 kg girl are sitting in identical office chairs in a large warehouse. The coefficients of static and kinetic friction between the chairs and the horizontal floor are both 0.250. The boy puts his feet up against the girl’s chair and p...

A minimum horizontal force of 10 N is needed to keep a 500 g book in place against a wall as shown.What maximum mass of book could be supported by the 10 N force if it were directed upwards at an angle of 60° instead of at right angles to the wall?