Phys Unit 7 -- Static Electricity Flashcards
(24 cards)
Define Static Charge.
An electric charge that can be collected and held in one place.
How many charges are there, and what are they? (remember, this is physics, not chemistry.)
Two. Positive and negative.
True or false: there is no neutral charge unless it is the overall charge.
True. (unlike chem, there is no +2 or -2, just neutral.)
What charge do protons hold? Electrons?
Protons are positive charge holders and electrons are negative charge holders.
What condition must apply to call an object “neutral charge?”
The number of protons and electrons must be the same.
What happens so that electric charge occurs?
The addition or removal of electrons.
Determine if the following is true or false. If false, amend the statement so it is true.
- Conductors do not allow electrons to flow easily.
- Insulators allow electrons to move freely.
False.
Answer:
1. Conductors allow electrons to flow easily.
2. Insulators do not allow electrons to move freely.
Name an example for a conductor.
Metals.
Name three examples of non-conductors.
Glass, plastic, ceramics.
How do objects become charged? Give an example.
Objects become charged by friction. Example: rubbing feet on the carpet.
Give the unit of the electrical charge and its letter.
Coulomb (C)
Which series helps you find out the tendency of losing or gaining electrons?
The triboelectric series.
Determine the charges for each item using the Triboelectric Series.
A balloon is rubbed with a paper towel. What is the charge of…
a) the balloon
b) the paper towel.
a) the balloon’s charge will be negative
b) the paper towel’s charge will be positive.
What instrument can generate static charge?
Van de Graaff Generator.
Where is the static charge produced on the Van de Graaff Generator?
The conveyor belt.
Define grounding.
Grounding allows charge to flow into the earth’s surface.
True or false: electrical appliances can be grounded by connecting a wire to the metal frame.
True.
What is electric force?
it is a push or pull.
On what two things does the electric force depend on?
- Distance between objects.
2. Amount of charge. (more is stronger, less is weaker.)
Name the three laws of static charge.
- Opposites attract.
- Like charges repel.
- Neutral objects are attracted to charged objects.
Define conduction:
Conduction is the process of transferring charge between objects by touching. (think of conductivity.)
Define induction:
Induction is the process of rearranging the electrons on a neutral object by bringing a charged object close to it.
Which law of static charge applies to induction?
Law 3: neutral objects are attracted to charged objects.
True or false: conduction needs contact and induction does not, but the result stays the same.
True.
