charging by induction: temporarily induced charge separation charging by induction when a charged...
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Charging by Induction
Charging by Induction: Temporarily
induced charge
separation
charging by
induction
When a charged object is brought close to,
but not touching, a neutral object, the
electrons in the neutral object move either
away from or toward the charged object.
When electrons move within an object
because of a nearby charged object, it is
called induced charge separation.
Charging by Induction: Temporarily
Once the charged object is moved away, the electrons in the neutral object return to their original positions.
Charging by Induction: Temporarily
You can permanently charge an object
using induction. To do this, you need to
ground the neutral object.
Charging by Induction: Permanently
Charging by Induction: Permanently
A negatively charged object is placed near a neutral object, causing the electrons to move.
__ __
Charging by Induction: Permanently
The neutral object is grounded, allowing the repelled electrons in the neutral object to escape to the ground. The neutral object loses electrons.
___
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Charging by Induction: Permanently
The ground is removed, leaving the ball with a positive charge.
___ _
If electrons move from the neutral object
through the wire to the ground (object loses
electrons), the object becomes positively
charged.
If electrons move from the ground through
the wire toward the object (object gains
electrons), the object becomes negatively
charged.
Charging by Induction: Permanently
Animation of Permanent Induction
Charging by Induction: Permanently
Applications of Static Electricity
ApplicationScience
principles involved
How the application works
Electrostatic speakers
charging by induction, law of electric charges
In an electrostatic speaker, an audio transformer induces opposite electrical charges on two outer plates (stators) and then (b) reverses them.
Note: Charging by Induction
This method of charging objects involves no contact between a charged object and a neutral object, and grounding is used.
Note: Charging by Induction
1.
Negative
Neutral
Note: Charging by Induction
1.
Negative
Neutrale-
Note: Charging by Induction1.A negatively charged rod is placed near a neutral object. The excess electrons in the rod repel the _____________ in the object making them move as far away from the rod as possible. This shifting of electrons makes one side of the object __________________ and the other side _________________ (however, the object is still neutral). This is called _____________________________.
electrons
positivenegative
induced charge separation
Note: Charging by Induction
2.
Negative
Ground
e-
Note: Charging by Induction
2.
If the neutral object is grounded, the repelled
electrons move from the ____________ to the
___________ (the object _________ electrons).
object
ground loses
Note: Charging by Induction
3.
Negative
Positive
Note: Charging by Induction
3.
When the ground is removed, the object is left
with a _____________ charge (because it
_________ electrons to the ground).
positive
lost
*** When objects are permanently
charged by induction, the induced
charge is always ______________
that of the charged object.
Note: Charging by Induction
opposite
Charging by Induction Questions1. Temporary Induction
A. A neutral metal-leaf electroscope.
B. A negatively charged object is placed near (not touching) the metal ball of a neutral metal-leaf electroscope.
C. The charged object has been removed.
Charging by Induction Questions1. Temporary Induction
A. A neutral metal-leaf electroscope.
B. A negatively charged object is placed near (not touching) the metal ball of a neutral metal-leaf electroscope.
C. The charged object has been removed.
e-
Charging by Induction Questions1. Temporary Induction
A. A neutral metal-leaf electroscope.
B. A negatively charged object is placed near (not touching) the metal ball of a neutral metal-leaf electroscope.
C. The charged object has been removed.
e-
Charging by Induction Questions1. Temporary Induction
A. A neutral metal-leaf electroscope.
B. A negatively charged object is placed near (not touching) the metal ball of a neutral metal-leaf electroscope.
C. The charged object has been removed.
e-
Charging by Induction Questions2. Permanent Induction
A. A positively charged object is placed near (not touching) a neutral electroscope.
B. The electroscope is then grounded.
C. The ground is removed. Then the charged object is removed.
Charging by Induction Questions2. Permanent Induction
A. A positively charged object is placed near (not touching) a neutral electroscope.
B. The electroscope is then grounded.
C. The ground is removed. Then the charged object is removed.
e-
e-
p. 489 # 2, 3, 4, 6
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