Chapter 5

The current in a 20-ohm electric heater operated at 240 V is

12 A

The current in a 24-W, 12-V light bulb is

2 A

Two 240-watt light bulbs are connected in parallel across a 120-V power line. The current in each bulb is

2.0 A

Two charges repel each other with a force of 1 x 10-6 N when they are 10 cm apart. When they are brought closer together until they are 2 cm apart, the force between them becomes

2.5 x 10-5 N

Three 12-V batteries cannot be connected to give a voltage for the set of

6 V

An electric iron draws a current of 15 A when connected to a 120-V power source. Its resistance is

8 ohms

Coulomb's formula F = KQ1Q2/R2 gives the force between two charges in free space. The value of K

is the same under all circumstances

A positive electric charge

repels other positive charges

An atom consists of a

small positive nucleus surrounded at a distance by electrons

A solid conductor is one

some of whose electrons are free to move about

A magnet attracts

some substances and repels others

A magnetic field does not interact with a

stationary electric charge