Unit III - Electricity and Magnetism

I. Static Electricity - electronic charges flowing in ______________________.

A) Electricity of the Atom - Electrical Charges come from the atom

Atoms are ordinarily neutral (#protons = ___________ )

Charge of electron = _______________Coulombs

1. *** Atoms become charged by gaining or losing________________.

Mg ^{+ 2} F ^{- 1}

Why are ______________________________ by an atom??

a) Ion – _____________________________________

· Negatively charged ion - _________________________

· Positive charge ________________________

2. Charged objects lose their charge when they are_______________

3.

· _____________ charged object ____________________when grounded to become neutral.

· _____________ charged object ___________________ when

______________to become __________.

B. Detecting electric fields.

1. Electroscope - used to detect presence of __________________.

a) if no charge is present leaves point _________________

b) leaves _____________________in presence of charge.

C) Transfer of charge

1. Charge can be transferred between neutral objects by

friction.

Ex) hard rubber rod rubbed with fur or wool causes electrons

to be transferred to rod.

Rod - _______________ ______ charge

wool, fur - ____________ _______ charge

2. Conduction - charging object through contact with a charged body.

Case I – Contact with a negative charging body

1. Neutral Electroscope 2. Contact with negative rod 3. Removal of Rod

Case II – Contact with a positive charging body