Q1. A container holds a gas consisting of 1.76 moles of oxygen molecules. One in a million of these molecules have lost a single electron. What is the net charge of gas?
Q2. How strong is the electric field between the plates of a 0.78 mu F air-gap capacitor if they are 3.0 mm apart and each has the charge of 77 mu C?
Q3. A 3.40 g coin is positioned 16.0 cm from the center of a turntable. The coin has static and kinetic coefficients of friction with the turntable surface of mu_s = 0.720 and mu_k = 0.480. What is maximum angular velocity with which the turntable can spin without the coin sliding?