Solving for distance between plates, diameter of a capacitor

[PhysicsMan999]

Homework Statement

1. 
   A 5.02 pF air-filled capacitor with circular parallel plates is to be used in a circuit where it will be subjected to potentials of up to 95 V. The electric field between the plates is to be no greater than 1.40×104 N/C. As an electrical engineer for Live-Wire Electronics, your task is to design the capacitor. What is its size? Enter the diameter and the separation of the plates.
   

Homework Equations

C=kEA/d
E=V/d
A=pir^2

The Attempt at a Solution

I used E=V/d to try and find the distance, then plugged that into the capacitance equation to find the area of the plates, which I then used to find the radius of the circle, which I multiplied by 2 to get the diameter.

 

[rude man]

Homework Statement

1. 
   A 5.02 pF air-filled capacitor with circular parallel plates is to be used in a circuit where it will be subjected to potentials of up to 95 V. The electric field between the plates is to be no greater than 1.40×104 N/C. As an electrical engineer for Live-Wire Electronics, your task is to design the capacitor. What is its size? Enter the diameter and the separation of the plates.

Homework Equations

C=kEA/d
E=V/d
A=pir^2

The Attempt at a Solution

I used E=V/d to try and find the distance, then plugged that into the capacitance equation to find the area of the plates, which I then used to find the radius of the circle, which I multiplied by 2 to get the diameter.

Just what I would have done! Congrats!

 

[PhysicsMan999]

CAPA says my answers are wrong though! The answers I'm getting are 0.00679 for the distance between plates, and around 0.07 for the diameter..

 

[gneill]

CAPA says my answers are wrong though! The answers I'm getting are 0.00679 for the distance between plates, and around 0.07 for the diameter..

Did the system specify particular units to use? Is it finicky about significant figures?

 

[PhysicsMan999]

Well, apparently I was entering them in the wrong order..even though it says nothing about the order to enter them in. Thanks!

 

[rude man]

CAPA says my answers are wrong though! The answers I'm getting are 0.00679 for the distance between plates, and around 0.07 for the diameter..

Well, I didn't check your math. I only endorsed your methodology!