Electrostatic force between charged and neutral object?

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Coulomb's Law indicates that the force of attraction between a charged and a neutral object is zero when calculating directly, as substituting zero for the charge of the neutral object results in zero force. However, the Law of Electrostatics suggests that a charged object can induce a charge on a neutral object, leading to attraction. When a charged particle approaches a neutral object, it induces opposite charges on the near surface, creating a net attractive force. The magnitude of this force is influenced by the dimensions of the neutral object. In cases where charge cannot be induced, such as with fixed electrons, the force may indeed be zero.
Dragynfyre
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Homework Statement



Well we just learned about Coulomb's Law today but there is something that is bothering me. According to Coulomb's Law the magnitude of the force of attraction between a charged and neutral object is 0. However, the Law of Electrostatics states that a charged and neutral object should attract each other. I'm wondering is there a special case for calculating the force of attraction when one object is neutral and the other is charged?

Homework Equations



Coulomb's Law

F=kq1q2/r2

The Attempt at a Solution



If 0 is substituted in for q1 in the equation the magnitude of the force becomes 0 no matter what the charge is on the second object.
 
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Hi Dragynfyre, welcome to PF.

When you bring a charged particle near a neutral object, opposite charge is induces on the near surface of the neutral object and the same charge on the far side of the neutral object. Due to this a net force is acting on the charged particle. The magnitude of the net force depends on the dimension of the neutral object.
 
Ahh okay but say there was an object where the electrons could not move and a charge can't be induced. For example the electrostatic force between a proton and neutron (I know there are quarks and other stuff but let's leave those out of this discussion). Would the force be 0?
 
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?

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