Electric Field and two point particles

Click For Summary
Two point particles separated by 0.4 m have a total charge of 185 µC and repel each other with a force of 80 N, resulting in charges of approximately 8.05 µC and 176 µC, despite not summing to 185 µC. When the particles attract each other with the same force, one charge must be negative, but the absolute values remain the same. The force calculation, using Coulomb's law, does not depend on the sign of the charges, only their magnitudes. The discussion emphasizes that the product of the charges' signs determines the direction of the force. Understanding these principles is crucial for solving problems involving electric fields and forces between charged particles.
fallen186
Messages
41
Reaction score
0

Homework Statement


Two point particles separated by 0.4 m carry a total charge of 185 µC.
(a) If the two particles repel each other with a force of 80 N, what are the charges on each of the two particles?
q1=8.05µC
q2=176 µC
*I know they don't add up to 185 but it took both of the answers as correct*
(b) If the two particles attract each other with a force of 80 N, what are the charges on the two particles?

I don't see why it wouldn't be the same answer except one of them would be negative.
According to F=k*\frac{|q_{1}*q_{2}|}{r^{2}}The type of charge doesn't matter when calculating force.
 
Physics news on Phys.org
fallen186 said:

Homework Statement


Two point particles separated by 0.4 m carry a total charge of 185 µC.
(a) If the two particles repel each other with a force of 80 N, what are the charges on each of the two particles?
q1=8.05µC
q2=176 µC
*I know they don't add up to 185 but it took both of the answers as correct*
(b) If the two particles attract each other with a force of 80 N, what are the charges on the two particles?

I don't see why it wouldn't be the same answer except one of them would be negative.
According to F=k*\frac{|q_{1}*q_{2}|}{r^{2}}The type of charge doesn't matter when calculating force.

The product of the signs determine direction, as you observed.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

Similar threads

Replies
9
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
23
Views
1K
Replies
14
Views
3K
  • · Replies 26 ·
Replies
26
Views
3K
Replies
3
Views
944
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 6 ·
Replies
6
Views
979
  • · Replies 68 ·
3
Replies
68
Views
8K