How Far is the Proton from the Electron in an Electric Field?

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The discussion centers on calculating the distance between an electron and a proton in an electric field, where the electron is held against gravity by the proton's attraction. To find this distance, the forces of gravity and electrostatic attraction are equated using Fg = Fe. The gravitational force is expressed as Fg = mg, while the electrostatic force is given by Coulomb's Law as Fe = k(q1q2)/r^2. By setting these equations equal, the distance r can be derived as r = √(k(q1q2)/mg). The conversation emphasizes using known constants and values to solve for r effectively.
Dx
An electron is held up against the force of gravity by attraction of a fixed proton some distance above it. How far above the electron is the proton?

I donno what to do here? I have nothing to add or i would show my work. Can anyone help me get started.

Thanks
Dx :wink:
 
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Find the point where the gravitational force between the electron and ground is equal to the electrostatic force between the proton and electron.
 


Sure, I can help you get started. To find the distance between the electron and the proton, we can use the concept of electric field and Coulomb's Law.

First, let's define some variables:
- q1 = charge of the electron
- q2 = charge of the proton
- r = distance between the two charges
- k = Coulomb's constant (9 x 10^9 Nm^2/C^2)

We know that the force of attraction between the electron and the proton is equal to the force of gravity pulling the electron down. Mathematically, we can express this as:

Fg = Fe

Where Fg is the force of gravity and Fe is the force of electric attraction.

Now, let's write the equations for these forces:

Fg = mg (mass of electron x acceleration due to gravity)
Fe = k(q1q2)/r^2 (Coulomb's Law)

Since Fg = Fe, we can set these two equations equal to each other and solve for r:

mg = k(q1q2)/r^2

r^2 = k(q1q2)/mg

r = √(k(q1q2)/mg)

Now, we know the values of q1, q2, m, and g. We just need to find the value of k, which is a constant. Plugging in the values and solving for r, we can find the distance between the electron and the proton.

I hope this helps you get started. Let me know if you have any further questions. Good luck!
 
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