Coulomb's Law: Calculating the Force between Two Charged Balls

In summary, the problem involves two small balls with charges of -2.6 nC and +1.2 nC located 2.5 cm apart. Using the formula F = k * (Q1 * Q2)/r2, where k = 8.99 * 10^9, Q1 = -2.6 nC, Q2 = +1.2 nC, and r2 = 0.00252, the force between the balls can be calculated. The book uses the notation 10^-9 to represent nC, which stands for nanocoulombs and is a unit of electric charge. It is not necessary to know the size or material of the balls for this calculation.
  • #1
Drizzy
210
1

Homework Statement



A small ball has been loaded so that its charge is -2.6 nC. Another similar ball has the charge +1.2 nC. The balls are located at the distance 2.5 cm from each other . With how much force do the balls attracts each other?

Homework Equations



F = k * (Q1 * Q2)/r2

The Attempt at a Solution



k = 8,99 * 109
Q1 = -2.6 n
Q2 = +1.2 n
r2 = 0,00252

F = 8,99 * 109 (-2.6 * 1.2)/0,00252
---------------------------------------------
This is what my book has written:

F = 8,99 * 109 (-2.6 * 10-9 1.2 * 10-9)/0,00252

So my question is: From where did they get 10-9?
 
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  • #2
Drizzy said:

Homework Statement



A small ball has been loaded so that its charge is -2.6 nC. Another similar ball has the charge +1.2 nC. The balls are located at the distance 2.5 cm from each other . With how much force do the balls attracts each other?

Homework Equations



F = k * (Q1 * Q2)/r2

The Attempt at a Solution



k = 8,99 * 109
Q1 = -2.6 n
Q2 = +1.2 n
r2 = 0,00252

F = 8,99 * 109 (-2.6 * 1.2)/0,00252
---------------------------------------------
This is what my book has written:

F = 8,99 * 109 (-2.6 * 10-9 1.2 * 10-9)/0,00252

So my question is: From where did they get 10-9?
What do you think nC means?
 
  • #3
It means how many electrons and atoms there is in the ball but how am I supposed to know how big the ball is and what material it is?
 
  • #4
Drizzy said:
It means how many electrons and atoms there is in the ball but how am I supposed to know how big the ball is and what material it is?
milli, micro, nano, pico, ... ring a bell?

You shouldn't care about the ball size or material. The problem says they are small so you can assume that their exact dimensions can be ignored and won't interfere with your calculations. In other words, assume that they won't touch or overlap when they are set 2.5 cm apart.
 
  • #5
oh yeah nano is 10-9 I thought n was the number of electrons in the object (lika a variable) but now I know what it is thank you for the help :)
 

1. What is Coulomb's law of a small ball?

Coulomb's law of a small ball is an equation that describes the electrostatic force between two charged particles. It states that the force is directly proportional to the product of the two charges and inversely proportional to the square of the distance between them.

2. What is the formula for Coulomb's law?

The formula for Coulomb's law is F = k(q1q2/r^2), where F is the electrostatic force, k is the Coulomb's constant, q1 and q2 are the charges of the two particles, and r is the distance between them.

3. How does the distance between two charged particles affect the electrostatic force?

The distance between two charged particles is inversely proportional to the electrostatic force according to Coulomb's law. This means that as the distance between the two particles increases, the force decreases, and vice versa.

4. What is the significance of the Coulomb's constant in the equation?

The Coulomb's constant, denoted by k, is a proportionality constant that relates the electrostatic force to the charges and distance between the particles. It has a value of 8.98755 x 10^9 Nm^2/C^2 and is used to calculate the force in the SI unit system.

5. How is Coulomb's law related to the concept of electric fields?

Coulomb's law is related to the concept of electric fields because it describes the force between two charges in terms of the electric field created by those charges. The electric field is a vector quantity that shows the direction and magnitude of the force experienced by a test charge placed in the field. Coulomb's law is used to calculate the strength of the electric field at a certain point in space.

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