Could we measure this force using the angle of deviation away from the rest position(in radians or in degrees)?

The main problem I can see with that is: what if something has more charge than the plate? It would only be able to pull it so far before there's no difference, yet the objects could have completely different fields!

How is a stick able to hold an electrical charge to produce static electricity? Also, what kind of ball is that and how does it become attracted to static?

I think Sal might have some videos on static electricity. That's a pith ball and it's made from the dry, spongy material found inside the stem of some plants. It holds electricity for the same reason that your hair stands on end when you rub a balloon through it. Hope that helps!

What if 2 balls (ignoring gravity) attached to a string and possessing same charge (say, +q) are suspended. What will be the angle (theta) between the strings and also tension in strings?

You said, "ignoring gravity." In electrics, where opposites attract, likes repel. The balls move apart. Unobstructed, the balls assume an orientation as far from each other as possible. This is likely a theta of 180º in your system. The key is the "why?" Theta is most useful, in the gravity case.

What is the "Pith Ball"? What is it made of?

This is a styrofoam ball, though you could also use a small piece cork.

Main content

Course: Physics library > Unit 18

Lesson 8: Electrostatics

Pith ball electroscope

Name: Pith ball electroscope
Uploaded: 2013-02-19T03:43:46Z
Description: Primitive device for measuring electrostatic force

Google Classroom

Primitive device for measuring electrostatic force. Created by Brit Cruise.

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eightsquare
Posted 11 years ago. Direct link to eightsquare's post “Could we measure this for...”
Could we measure this force using the angle of deviation away from the rest position(in radians or in degrees)?
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- bennette1916
  Posted 11 years ago. Direct link to bennette1916's post “The main problem I can se...”
  The main problem I can see with that is: what if something has more charge than the plate? It would only be able to pull it so far before there's no difference, yet the objects could have completely different fields!
  Comment on bennette1916's post “The main problem I can se...”
  (6 votes)
maceden
Posted 10 years ago. Direct link to maceden's post “That was cool. But did an...”
That was cool. But did any of you see that as the guy was rubbing the plate on the cat, the cat got up and tried to get away? LOL I would too. ;)
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(14 votes)
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♦SamuelM♦
Posted 11 years ago. Direct link to ♦SamuelM♦'s post “How is a stick able to ho...”
How is a stick able to hold an electrical charge to produce static electricity? Also, what kind of ball is that and how does it become attracted to static?
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(6 votes)
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- ♘¢áىŢ£ε ¢øىאŢrú¢tør♘
  Posted 11 years ago. Direct link to ♘¢áىŢ£ε ¢øىאŢrú¢tør♘'s post “I think Sal might have so...”
  I think Sal might have some videos on static electricity.
  That's a pith ball and it's made from the dry, spongy material found inside the stem of some plants. It holds electricity for the same reason that your hair stands on end when you rub a balloon through it. Hope that helps!
  Button navigates to signup page
  (6 votes)
cjrlamb
Posted 11 years ago. Direct link to cjrlamb's post “we could measure the forc...”
we could measure the force in a standard unit by adding weight to the Styrofoam ball and then test how powerful the static is by how much weight it could hold
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ayushi1300
Posted 11 years ago. Direct link to ayushi1300's post “What if 2 balls (ignoring...”
What if 2 balls (ignoring gravity) attached to a string and possessing same charge (say, +q) are suspended. What will be the angle (theta) between the strings and also tension in strings?
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(3 votes)
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- Exponentially Radical
  Posted 11 years ago. Direct link to Exponentially Radical's post “You said, "ignoring gravi...”
  You said, "ignoring gravity." In electrics, where opposites attract, likes repel. The balls move apart. Unobstructed, the balls assume an orientation as far from each other as possible. This is likely a theta of 180º in your system. The key is the "why?"
  Theta is most useful, in the gravity case.
  Button navigates to signup page
  (4 votes)
ƝaŦhanieɭ
Posted 11 years ago. Direct link to ƝaŦhanieɭ's post “What is the "Pith Ball"? ...”
What is the "Pith Ball"? What is it made of?
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(3 votes)
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- brit cruise
  Posted 11 years ago. Direct link to brit cruise's post “This is a styrofoam ball,...”
  This is a styrofoam ball, though you could also use a small piece cork.
  Comment on brit cruise's post “This is a styrofoam ball,...”
  (2 votes)
Kakashi
Posted 11 years ago. Direct link to Kakashi's post “how could we measure this...”
how could we measure this force with unit standard unit?
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(2 votes)
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gupta.indresh
Posted 11 years ago. Direct link to gupta.indresh's post “What happens when you the...”
What happens when you the pipe like structure to the cats fur?
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(1 vote)
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gupta.indresh
Posted 11 years ago. Direct link to gupta.indresh's post “What is the material is t...”
What is the material is the man rubbing against the cat, which he uses it to attract the styrofoam ball?
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- Exponentially Radical
  Posted 11 years ago. Direct link to Exponentially Radical's post “Brit used plastic straw t...”
  Brit used plastic straw then a plastic plate.
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  (1 vote)
gupta.indresh
Posted 11 years ago. Direct link to gupta.indresh's post “Then do paper plates has ...”
Then do paper plates has any charge?
If so can we use normal reading paper?
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