ELECTRICAL CHARGE Ch. 32

Electrical charge When the comb is brought closer to the bits of paper, a charge separation is induced on the paper bits.

Charge interaction

Coulomb’s law F = K qAqB d2 The force between two charges is proportional with the two charges, and inversely proportional with the squared distance between the charges

Electric force: the force between electric charges

Structure of the atom

Identify the following particles as being charged or uncharged Identify the following particles as being charged or uncharged. If charged, indicate whether they are charged positively or negatively. (n = neutron, p = proton, e = electron)

Conductors and insulators

Polarization

Charged rubber rods are placed near a neutral conducting sphere, causing a redistribution of charge on the spheres. Which of the diagrams below depict the proper distribution of charge on the spheres? List all that apply. Diagram E shows the metal sphere with an overall positive charge. This should never happen. Diagrams B and C show the charge on the rubber rod attracting the like charge on the sphere. But since likes repel, this could never happen. Diagrams A and D properly show the charge distribution with the charge on the rod attracting the opposite type of charge which is present on the sphere.

Charging by friction / induction

Charging by conduction

grounding

ELECTRIC FIELDS Ch. 33

Electric fields

Van de Graaff generator

Consider the electric field lines shown in the diagram below Consider the electric field lines shown in the diagram below. From the diagram, it is apparent that object A is ____ and object B is ____. a. +, + b. -, - c. +, - d. -, + e. insufficient info

Several electric field line patterns are shown in the diagrams below Several electric field line patterns are shown in the diagrams below. Which of these patterns are incorrect? Explain what is wrong with all incorrect diagrams.

Lightening