# How Do Electrical Forces Interact in Physics Problems?

• seiferseph
In summary, electrical forces refer to the interactions between charged particles and are much stronger and more versatile than other types of forces. Coulomb's Law describes the relationship between electrical forces, charge, and distance, and these forces play a crucial role in determining the behavior of matter. They can also be harnessed for practical applications in various industries and in scientific research.
seiferseph
I have some more questions from a physics worksheet, this time on electrical forces. here are the questions and the answers i got, thanks in advance!

Questions:
http://i2.photobucket.com/albums/y15/seiferseph/electircalforces.jpg

1) Fe = kQq/R^2, i get 3.6 x 10^10 N
2) a) Fg = GMm/R^2, i get 7.80 x 10^-47 N
b) Fe = kQq/R^2, using 1.6x10^-19 for both Q and -1.6x10^-19 for q, i get Fe = -8.86x10^-8 N
3) Q = n*e, Q/e = n. n = 2.5x10^19. i have a question though, can it be negative? (the charge is negative)
4) How do i do this one? is it just a simple ratio problem?
5) a) i calculated the force of each one seperately, i used 2*1.6x10^-19 for the charge of the middle one, because it has two protons.
F 1 on middle = k*q1*qmiddle/R^2 = 3.2x10-16
F 2 on middle = k*q2*qmiddle/R^2 = 1.44x10-15
and i get 1.76x10^15 N to the right
b) F = m*a, F/m = a, where m is 4*1.67x10^-27 = 2.6x10^11 m/s^2

thanks!

Last edited by a moderator:
seiferseph said:
I have some more questions from a physics worksheet, this time on electrical forces. here are the questions and the answers i got, thanks in advance!

Questions:
http://i2.photobucket.com/albums/y15/seiferseph/electircalforces.jpg

3) Q = n*e, Q/e = n. n = 2.5x10^19. i have a question though, can it be negative? (the charge is negative)
4) How do i do this one? is it just a simple ratio problem?
5) a) i calculated the force of each one seperately, i used 2*1.6x10^-19 for the charge of the middle one, because it has two protons.
F 1 on middle = k*q1*qmiddle/R^2 = 3.2x10-16
F 2 on middle = k*q2*qmiddle/R^2 = 1.44x10-15
and i get 1.76x10^15 N to the right
b) F = m*a, F/m = a, where m is 4*1.67x10^-27 = 2.6x10^11 m/s^2

thanks!

1) 2) Correct approach.. did not check your computations
3) The negative charge comes from negatively charged electrons. The NUMBER of electrons is positive.

4) Yes. You can find the charge to mass ratio for one electron.

5) a) Are these forces in opposite directions?
b) There is no b showing

Last edited by a moderator:

1) Your calculation for the electrical force between the two charges is correct. However, it is important to note the direction of the force, which would be repulsive in this case since both charges are positive. So the correct answer would be 3.6 x 10^10 N to the right.

2)a) Your calculation for the gravitational force is correct. However, it is important to note that this is a very small force due to the extremely small masses of the particles involved.

b) Your calculation for the electrical force is also correct. Again, it is important to note the direction of the force, which would be attractive in this case since one charge is positive and the other is negative.

3) Your calculation for the number of electrons is correct, and yes, the charge can be negative in this case since it represents the charge of an electron.

4) For this question, you can use Coulomb's Law to calculate the electrical force between the two charges. Simply plug in the values given for Q and q, and then solve for the force.

5)a) Your calculations for the electrical forces are correct. However, when adding them together, it is important to consider the direction of the forces as well. Since both forces are to the right, the total force would be 1.76 x 10^15 N to the right.

b) Your calculation for the acceleration is correct. However, it is important to note that this is an extremely high acceleration, which is not likely to occur in real-life situations.

Overall, your calculations and answers are correct. Just make sure to pay attention to the direction of the forces and to use the correct values for the charges in your calculations. Keep up the good work!

## 1. What are electrical forces in physics?

Electrical forces refer to the attractive or repulsive interactions between electrically charged particles, such as electrons and protons.

## 2. How are electrical forces different from other types of forces?

Electrical forces are unique in that they are much stronger than other types of forces, such as gravitational or magnetic forces. They also have the ability to both attract and repel, depending on the charge of the particles involved.

## 3. What is Coulomb's Law and how does it relate to electrical forces?

Coulomb's Law is a fundamental principle in physics that describes the relationship between electrical forces, charge, and distance. It states that the force between two charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them.

## 4. How do electrical forces affect the behavior of matter?

Electrical forces play a crucial role in determining the structure and behavior of matter. For example, they are responsible for holding atoms together in molecules and determining the properties of materials such as conductivity and magnetism.

## 5. Can electrical forces be harnessed for practical applications?

Yes, electrical forces are harnessed in a wide range of practical applications, including electronics, power generation, and medical technology. They are also utilized in fundamental research to study the behavior of matter and the universe.

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