Summary of Electromagnetism

The electrical force of attraction between an electron and a

proton is greater on the

• proton.

• electron.

• Neither; both are the same.

When you brush your hair and scrape electrons from your hair,

the charge of your hair becomes

• positive.

• negative.

• Both of these.

• Neither of these.

According to Coulomb, a pair of charged particles placed twice as close to each other experience a force

• twice as strong.

• four times as strong

• half as strong

• one-fourth as strong

When you buy a pipe in a hardware store, the water isn’t

included. When you buy copper wire, electrons

• must be supplied by you

• are included in the wire

• may fall out—hence insulation

• None of these

Immediately after two separated charged particles are released from rest, both increase in speed. The sign of charge of the particles is therefore

• the same

• opposite

• Either of these

• Need more information

Immediately after two separated charged particles are released from rest, both increase in acceleration. The sign of charge of the particles is therefore

• the same

• opposite

• Either of these

• Need more information

The electric field between a pair of oppositely charged parallel plates

• gets weaker with distance inside the plates

• follows the inverse-square law

• Both of these

• Neither of these

A capacitor can store

• charge

• energy

• Both of these

• Neither of these

The electric field inside the dome of a Van de Graaff generator is zero when the dome is

• charged

• uncharged

• Either of these

• Neither of these

The potential energy of a compressed spring and the potential energy of a charged object both depend on

• the work done on them

• motion

• Both of these

• Neither of these