httpsyoutubeyc2 363MIQs Whiteboard Review Questions Whiteboard Practice An initially neutral balloon acquires negative charge after it is rubbed against a mans hair which was also initially neutral What charge does the mans hair have now positive negative or neutral Why ID: 557220
Download Presentation The PPT/PDF document "Static Electricity Review" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
Static Electricity Review
https://youtu.be/yc2-
363MIQsSlide2
Whiteboard Review QuestionsSlide3
Whiteboard Practice
An initially neutral balloon acquires negative charge after it is rubbed against a man’s hair (which was also initially neutral). What charge does the man’s hair have now: positive, negative, or neutral? Why?Slide4
Whiteboard Practice
What is the difference between a material that is a good insulator and a material that is a good conductor, in terms of its atoms?Slide5
Whiteboard Practice
A neutral conducting sphere is connected to the ground with a conducting wire. A negatively charged rod is brought near the sphere and then leaves without touching it. What charge does the sphere have on it now?Slide6
Whiteboard Practice
A negatively-charged balloon is brought near a neutral electroscope, but does not touch it. Illustrate what happens to the charges inside the electroscope and how the leaves at the bottom will react.Slide7
Whiteboard Practice
Illustrate what happens to an aluminum can when a negatively-charged balloon is brought next to it. Is it attracted or repelled?Slide8
Whiteboard Practice
Illustrate what happens to an aluminum can when a positively-charged balloon is brought next to it. Is it attracted or repelled?Slide9
Whiteboard Practice
Illustrate what happens to a piece of wood (an insulator) when a negatively-charged comb is brought next to it. Is it attracted or repelled?Slide10
Whiteboard Practice
Two charged objects attract each other. If the amount of charge on one object doubles and the other triples, what would happen to the electrostatic force between them?Slide11
Whiteboard Practice
Two charged objects repel each other. If the amount of charge on one object is reduced by a factor of 4 and the distance between the objects is reduced by a factor of 8, what would happen to the electrostatic force between them?Slide12
Whiteboard Practice
Make your own problem. You may change either or both of the charges and/or the distance by any factor.Slide13
Coulomb’s Law Mathematics
Electrostatic Force MathematicsSlide14
Charge is measured in “Coulombs”
The unit for how much electrical charge is measured in
Coulombs (C)
.
A proton has a charge of 1.60 x 10
-19
C.
An electron has a charge of -
1.60 x 10
-19
C.Slide15
Charge is measured in “Coulombs”
The unit for how much electrical charge is measured in
Coulombs (C)
.
q
p
= +1.60 x 10
-19
C
q
e
= -1.60 x 10
-19
CSlide16
What is a “Coulomb?”
How many electrons does it take to make a charge of -1.0 C?
-1.6 x 10
-19
C / electronSlide17
What is a “Coulomb?”
How many electrons does it take to make a charge of -1.0 C?
-1.6 x 10
-19
C / electron
-1.0 CSlide18
What is a “Coulomb?”
How many electrons does it take to make a charge of -1.0 C?
-1.6 x 10
-19
C / electron
-1.0 C
= 6.25 x 10
-18
electronsSlide19
What is a “Coulomb?”
How many electrons does it take to make a charge of -1.0 C?
-1.6 x 10
-19
C / electron
-1.0 C
= 6.25 x 10
-18
electrons
Often, we represent charges in terms of
“
micro-Coulombs” (
μC
= 10
-6
C)
or
“
nano
-Coulombs” (
nC
= 10
-9
C)Slide20
Coulomb’s Law Math ExamplesSlide21
Example 1:
What’s the force between an electron and a proton that are 1 x 10-10 m apart?Slide22
Example 2:
Two charges, +6.0nC each, repel each other with a force of 1.0 N. How far apart are they?