Question

PHYS 1122 Homework 1 1. The figure below shows 5 sets of tiny spheres with a net charge on them. The spheres are equidistant along the axis. All the values of the net charge are given, except for the middle sphere, which has the same charge in all sets. Rank the sets by the magnitude of the total electrostatic force on the middle sphere, least to greatest a) b) +e c) +e +e +e d) +e +e e) +e te 2. If water has 10 electrons per atom (1 from each hydrogen, 8 from the oxygen), there are 18 g of water per mole and Avogadro's number (6.022 x 1023) of atoms per mole, how many grams of water do you need to have one Coulomb of charge from electrons? 3. Let's see how the strength of the electrical force compares to the gravitational force. If two 10 g ice cubes of pure water were a distance r apart. If we placed the same amount of excess charge on each ice cube, how much excess charge would we need so that the magnitude of the electrical force was the same as the gravitational force between them? 4. Two charged particles are 20 cm apart. The first has charge-2 μC and the second has charge +2 pC Halfway between the particles, give the electric field in unit vector notation. 5. If d-1 um, for the distribution of charge given in the figure, find the magnitude of electric field at point P if q1-q2 +10e, q3 +2e and q4 -20e 6. Can you use induction to produce a net charge on an insulator? Why or why not? 72 7. Two small charged objects with +2 HC and +12 HC are kept stationary by a a) b) 4 N on each object, in the necessary directions What is the free body diagram on each object? What must the distance be between the objects? A thin rod, with charge per unit length λ has length L. What is the electric field, in unit vector notation, a distance d away from one of its ends, perpendicular to the axis of the rod? 8.

Answer 1

HOMEWORKLIB POLICY one question at a time please.

F_1 = Kqe/d^2 = F_2 F_3 = Kq/(2d)^2 = F_4 F_1 = F_2, F_3 = F_4 Net force = 0 Net force = F_1 + F_2 = 2Kqe/d^2 Net force = F_3 + F_4 = 2Kqe/4 d^2 = Kq/2d^2 Net force = F_1 + F_2 + F_3 + F_4 = 2Kqe/d^2 + Kq/2d^2 = 5/2 Kqe/d^2 Net force = F_1 - F_2 + F_3 - F_4 = 0 Ranking (a) = (e) < (c) < (b) < (d) (a) = (e) least (d) greatest