Electrostatics - Lesson 1

1. ____ are the charged parts of an atom.

• Only electrons

• Only protons

• Neutrons only

• Electrons and neutrons

• Electrons and protons

TRUE or FALSE: An object that is positively charged contains all protons and no electrons.

• True

• False

TRUE or FALSE: An object that is negatively charged could contain only electrons with no accompanying protons.

• True

• False

TRUE or FALSE: An object that is electrically neutral contains only neutrons.

• True

• False

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)

• A is negatively charged

• A is positively charged

• B is uncharged

• C is negatively charged

• C is positively charged

Consider the graphic at the right of a neutral oxygen atom.

• a. Explain what must happen in order for the oxygen atom to become negatively charged.

• b. Explain what must happen in order for the oxygen atom to become positively charged.

Determine the quantity and type of charge on an object that has 3.62 x 10¹² more protons than electrons.

• +5.8 x 10^-7 Coulombs (rounded)

• -5.8 x 10^-7 Coulombs (rounded)

Complete the following statements:

After some rather exhausting counting (and a rather tall tale), a physics teacher determines that a very small sample of an object contains ...

• a. ... 8.25749 x 10¹⁷ protons and 5.26 x 10¹⁴ electrons; the charge on this object is ____ Coulombs.

• b. ... 3.12 x 10¹⁴ protons and 4.5488 x 10¹⁶ electrons; the charge on this object is ____ Coulombs.

• c. ... 2.40277 x 10¹⁹ protons and 9.88 x 10¹⁶ electrons; the charge on this object is ____ Coulombs.

• d. ... 2.6325 x 10¹⁵ protons and 2.6325 x 10¹⁵ electrons; the charge on this object is ____ Coulombs.

The amount of charge carried by a lightning bolt is estimated at 10 Coulombs. What quantity of excess electrons is carried by the lightning bolt?

• 6.25 x 10¹⁹ electrons

• 6.25 x 10¹⁵ electrons

Use your understanding of charge to answer the following questions. 1. Electrical forces ____.

• can cause objects to only attract each other

• can cause objects to only repel each other

• can cause objects to attract or repel each other

• have no effect on objects