A 70 kg man walks along a 40 kg horizontal plank which is 2 m long. The plank is attached to a hinge mounted to one wall, and the far end is supported by a vertical wire which is attached to an anchor in the ceiling. The wire can just barely support the man's full weight without snapping.
a) What is the maximum distance that the man can walk along the plank without the wire snapping?
b) What is the force provided by the hinge on the wall when the man is at this maximum distance?