Electric Field of 2 charges on x-axis

[notaphysmajor]

Homework Statement

Homework Equations

|E| = (Kq)/r^2

The Attempt at a Solution

I'm not really sure if there is a difference between part (a) and part (b)

 

[BvU]

Hello NPM,

well, from your relevant equation I wouldn't be able to see a difference! You need something more, about the direction perhaps !

Can you sketch the fields close to the charges in the two cases (there the 'other charge' hasn't got much influence) ?

 

[berkeman]

Homework Statement

Homework Equations

|E| = (Kq)/r^2

The Attempt at a Solution

I'm not really sure if there is a difference between part (a) and part (b)

They are very different. Why?