When a point mass m with charge q is constrained to move along a frictionless line (up and down) with a charge Q at the botton with the same sign as q. Show that the particle is in equilibrium at position y0 = p kqQ=(mg).

Awoman holds a book by placing it between her hands such that she presses at right angles to the front and back covers. the book has a mass of m = 1.8 kg and the coefficient of static friction between her hand and the book is μs = 0.67. no attempt 50% part (a) what is the weight of the book, fgb in newtons?