Electric Force Between Point Charges - AP Physics 2
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Two charges are placed a certain distance apart such that the force that each charge experiences is 20 N. If the distance between the charges is doubled, what is the new force that each charge experiences?
Two charges are placed a certain distance apart such that the force that each charge experiences is 20 N. If the distance between the charges is doubled, what is the new force that each charge experiences?
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To solve this problem, we'll need to utilize the equation for the electric force:
We're told that the force each charge experiences is 20 N at a certain distance, but then that distance is doubled. Thus, the new electric force will be:
To solve this problem, we'll need to utilize the equation for the electric force:
We're told that the force each charge experiences is 20 N at a certain distance, but then that distance is doubled. Thus, the new electric force will be:
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What is the force experienced by a 
point charge 
away from a 
point charge?
What is the force experienced by a
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The equation to find the force from two point charges is called Coulomb's Law.
In this equation, 
is force in Newtons, 
is the respective charge value in 
, 
is radius in meters, and 
is the Coulomb constant, which has a value of 
.
Now, we just plug in the numbers. Note: the charge values are in microcoulombs (the Greek letter 
, called "mu," stands for micro), which is equal to 
.
Therefore, the force experienced on either charge is 0.216N of force.
The equation to find the force from two point charges is called Coulomb's Law.
In this equation,
Now, we just plug in the numbers. Note: the charge values are in microcoulombs (the Greek letter
Therefore, the force experienced on either charge is 0.216N of force.
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Two objects in space are placed 
apart. One has a charge of 
, the second has a charge of 
. What is the electric force between them?
Two objects in space are placed
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Use Coloumb's law:
First, convert the charges into coulombs.
Plug in values into Coulomb's law.
Negative electric forces indicate attractive forces. Alternatively, we can reason that since one charge is positive, and the other is negative, the charges will attract.
Use Coloumb's law:
First, convert the charges into coulombs.
Plug in values into Coulomb's law.
Negative electric forces indicate attractive forces. Alternatively, we can reason that since one charge is positive, and the other is negative, the charges will attract.
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You have two point charges, 
and 
, 3m away from each other. The value of 
is 
, and the force they both experience is 
. What is the value of 
?
You have two point charges,
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The equation for the force between two point charges is as follows:
We have the values for 
, 
, 
, and 
, so we just need to rearrange the equation to solve for 
, then plug in the values we have.
Therefore, the value for the second charge is 
.
The equation for the force between two point charges is as follows:
We have the values for
Therefore, the value for the second charge is
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A point charge of Q sits at rest next to another charge of 3Q at a distance of R away. How does the force on Q from 3Q compare with the force on 3Q from Q?
A point charge of Q sits at rest next to another charge of 3Q at a distance of R away. How does the force on Q from 3Q compare with the force on 3Q from Q?
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Newton's third law states that any force interactions between two bodies must be equal. This is not so simple when another body is introduced. However, with two bodies, any force that acts on the other will have an equal and opposite reaction force.
Newton's third law states that any force interactions between two bodies must be equal. This is not so simple when another body is introduced. However, with two bodies, any force that acts on the other will have an equal and opposite reaction force.
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A point charge of Q and speed v heads towards another charge of 3Q. Assume the charges are relatively close to one another How does the force on Q from 3Q compare with the force on 3Q from Q?
A point charge of Q and speed v heads towards another charge of 3Q. Assume the charges are relatively close to one another How does the force on Q from 3Q compare with the force on 3Q from Q?
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Newton's third law states that any force interactions between two bodies must be equal. This is not so simple when another body is introduced. However, with two bodies, any force on acts on the other will have an equal and opposite reaction force. The fact that one of the bodies is moving is irrelevant when considering the relative magnitudes of the Newton's Third law pair.
Newton's third law states that any force interactions between two bodies must be equal. This is not so simple when another body is introduced. However, with two bodies, any force on acts on the other will have an equal and opposite reaction force. The fact that one of the bodies is moving is irrelevant when considering the relative magnitudes of the Newton's Third law pair.
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If charge 
has a value of 
, and charge 
has a value of 
, and the distance between their centers, 
, is 
what will be the magnitude of the force on charge 
?
If charge
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Using coulombs law to solve
Where:
it the first charge, in coulombs.
is the second charge, in coulombs.
is the distance between them, in meters
is the constant of 
Converting 
into 
Plugging values into coulombs law
The magnitude will be the absolute value.
Using coulombs law to solve
Where:
Converting
Plugging values into coulombs law
The magnitude will be the absolute value.
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If charge 
has a value of 
, and charge 
has a value of 
, and the distance between their centers, 
, has a value of 
, what will be the force on charge 
?
If charge
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Using coulombs law to solve
Where:
it the first charge, in coulombs.
is the second charge, in coulombs.
is the distance between them, in meters
is the constant of
Converting into
Plugging values into coulombs law
Magnitude will be the absolute value
Using coulombs law to solve
Where:
Converting
Plugging values into coulombs law
Magnitude will be the absolute value
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
What is the magnitude of the force on 
due to 
?
Charge
Charge
The distance between their centers,
What is the magnitude of the force on
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Using the electric field equation:
Where 
is 
is charge 
, in 
is charge 
, in
is the distance, in 
.
Convert 
to 
and plug in values:
Magnitude is equivalent to absolute value:
Using the electric field equation:
Where
Convert
Magnitude is equivalent to absolute value:
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
What is the magnitude of the force on 
due to 
?
Charge
Charge
The distance between their centers,
What is the magnitude of the force on
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Use Coulomb's law:
Where is 
is charge 
, in Coulombs
is charge 
, in Coulombs
is the distance, in meters.
Convert to and plug in values:
Magnitude is equivalent to absolute value:
Use Coulomb's law:
Where
Convert
Magnitude is equivalent to absolute value:
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
What is the magnitude of the force on 
due to 
?
Charge
Charge
The distance between their centers,
What is the magnitude of the force on
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Using Coulomb's law:
Where is 
is charge , in Coulombs
is charge , in Coulombs
is the distance, in meters.
Convert to and plug in values:
Magnitude is equivalent to absolute value:
Using Coulomb's law:
Where
Convert
Magnitude is equivalent to absolute value:
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
What is the magnitude of the force on 
due to 
?
Charge
Charge
The distance between their centers,
What is the magnitude of the force on
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Using Coulomb's law:
Where is 
is charge , in Coulombs
is charge , in Coulombs
is the distance, in meters.
Convert to and plug in values:
Magnitude is equivalent to absolute value:
Using Coulomb's law:
Where
Convert
Magnitude is equivalent to absolute value:
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
Determine the magnitude of the electric force on 
due to 
.
Charge
Charge
The distance between their centers,
Determine the magnitude of the electric force on
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Use Coulomb's law:
Where is 
is charge , in
is charge , in
is the distance, in .
Convert to and plug in values:
Magnitude is equivalent to absolute value:
Use Coulomb's law:
Where
Convert
Magnitude is equivalent to absolute value:
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Charge 
has a charge of 
Charge 
has a charge of 
The distance between their centers, 
is 
.
What is the magnitude of the force on 
due to 
?
Charge
Charge
The distance between their centers,
What is the magnitude of the force on
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Use Coulomb's law:
Where is 
is charge , in
is charge , in
is the distance, in .
Convert 
to and plug in values:
Magnitude is equivalent to absolute value:
Use Coulomb's law:
Where
Convert
Magnitude is equivalent to absolute value:
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Two 
nuclei are 
apart. Determine the magnitude of the electrical force of one on the other.
Two
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Use Coulombs Law:
Where 
Convert 
to 
and plug in values:
Use Coulombs Law:
Where
Convert
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How will the force between two positively charged objects change as they are brought closer together?
How will the force between two positively charged objects change as they are brought closer together?
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k
k
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Charge A and B are 
apart. If charge A has a charge of 
and a mass of 
, charge B has a charge of 
and a mass of 
, determine the acceleration of A due to B.
Charge A and B are
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Using Coulomb's law:
Using
Combining equations:
Converting 
to 
and 
to 
and plugging in values:
Using Coulomb's law:
Using
Combining equations:
Converting
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Charge A and B are 
apart. If charge A has a charge of 
and a mass of 
, charge B has a charge of 
and a mass of 
, determine the acceleration of B due to A.
Charge A and B are
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Using Coulomb's law:
Using
Combining equations:
Converting to and to and plugging in values:
Using Coulomb's law:
Using
Combining equations:
Converting
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Two electrons are deep in space and 
apart. Determine the force of one electron on the other.
Two electrons are deep in space and
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Using
Plugging in values:
Using
Plugging in values:
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A mobile 
, 
charge is perfectly balanced on top of a stationary 
charge. What will be the equilibrium height of the mobile charge?
A mobile
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Using
Combining equations and plugging in values:
Solving for 
Using
Combining equations and plugging in values:
Solving for
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