# Calculating the voltage and electric field strength between two parallel plates

## Homework Statement

- How much is the electrical voltage U between two evenly electrified parallel flat plates, distanced d = 1 cm, if the strength of electric field between them is E = 1 V / m? - - What is the strength of electric field to the left and to the right of each plate?
- What is the force on the surface (area) unit between the two plates?
- What are the voltage between the plates and the force on the surface unit as a result of doubling the distance between the two plates?
- How is the strength of the electric field and force between the two plates altered (changed), if the voltage is maintained constant?
Influencing constant is ε(0) = 8.85 × 10^-12 As / Vm.

V= E*d
F= Q*E
V= Qd/ Aε(0)
E= Q/ Aε(0)

## The Attempt at a Solution

First part: How much is the electrical voltage U between two evenly electrified parallel flat plates?

V= 1 V/m* 0.01 m= 0.01 V

Are my calculations for the first part correct?

And I really don't know how to approach the rest of the problem. Can someone please help me? Any hints?

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berkeman
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## Homework Statement

- How much is the electrical voltage U between two evenly electrified parallel flat plates, distanced d = 1 cm, if the strength of electric field between them is E = 1 V / m? - - What is the strength of electric field to the left and to the right of each plate?
- What is the force on the surface (area) unit between the two plates?
- What are the voltage between the plates and the force on the surface unit as a result of doubling the distance between the two plates?
- How is the strength of the electric field and force between the two plates altered (changed), if the voltage is maintained constant?
Influencing constant is ε(0) = 8.85 × 10^-12 As / Vm.

V= E*d
F= Q*E
V= Qd/ Aε(0)
E= Q/ Aε(0)

## The Attempt at a Solution

First part: How much is the electrical voltage U between two evenly electrified parallel flat plates?

V= 1 V/m* 0.01 m= 0.01 V

Are my calculations for the first part correct?

And I really don't know how to approach the rest of the problem. Can someone please help me? Any hints?
Yes, V = 0.01V is correct for the first part. The other equation that you will need is Q = CV. That should give you what you need for the rest.

Thank you for helping!

Second part: What is the strength of electric field to the left and to the right of each plate?

I need some help with this part. Any hints?

Third part: What is the force on the surface unit between the two plates?

E= ½ Q*V → Q= 2E/ V
Q= 200 C

F= Q*E= 200 N

Fourth part: What are the voltage between the plates and the force on the surface unit as a result of doubling the distance between the two plates?

d= 2 cm= 0.02 m

V= d*E= 0.02 V
Q= 2E/ V= 100 C
F= Q*E= 100 N

ARE MY CALCULATIONS CORRECT?

Fifth part: How is the strength of the electric field and force between the two plates altered (changed), if the voltage is maintained constant?

I need some help with this part. Any hints?

Thank you for helping!

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