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