Help with electric field problems

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To support an electron against gravity on Earth, the strength of the electric field can be calculated using the force equation F = qE, where the gravitational force on the electron is equal to its weight (F = mg). The charge of the electron is known, and the gravitational acceleration on Earth's surface is approximately 9.81 m/s². For the second problem, the acceleration of a proton in an electric field of 1 x 10^4 N/C can be determined using Newton's second law, F = ma, where the force acting on the proton is also calculated using F = qE. Clarification on the gravitational force and the specific values for mass and charge is necessary to solve these problems accurately. Understanding these fundamental principles will aid in solving the electric field problems presented.
fishboy39
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I have two electric field problems that I need help solving:

1. How strong an electric field is needed to support an electron against gravity on the surface of the earth?

I know the charge of an electron is -1.60 x 10^-19C
I think that you use the equation V=Ed, but I don't know what to do for the d dealing with earth.

2. What is the acceleration of a proton in an elctric field of 1 x 10^4 N/C?

This one I have no idea where to start. This problem is unlike any of the others that were given. It might deal with KE, but I'm not sure.

Any help would be greatly appreciated!
 
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1. Gravity exerts some force on the electron. Also, an electric field will exert a force given by: F = qE. Can you see where this is going?

2. What force must then act on the proton? Use Newton's second law to find the acceleration.
 
Still not sure

Using F=qE I know the q What is the F then? Is there a certain number for the gravity on the surface of the earth?

I know that F= ma, but I'm not sure where to go from this any other help would be appreciated
 

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