What Are the Correct Base Units for Electric Field?

[Kathi201]

A possible set of units of electric field, E, in terms of base units is:

a) kg x m x s^-1 x C^-2
b) kg x m^2 x s^-2 x C^-1
c) kg x m x s^-2 x C^-1
d) C x s^-1
e) N x C^-1

I believe it is E but i wondering if there is somthing I am missing. This is how I came up with that answer

E = kq/r^2

E = Nm^2/C^2 x C / m^2
= Nm^2 x C / C^2 x m^2

It says to use base units so for Newton am i suppose to incorporate a kg? I know that the unit for E is N/C but this problem just seems like it would be too easy if that was the answer

 

[alphysicist]

Hi Kathi201,

A possible set of units of electric field, E, in terms of base units is:

a) kg x m x s^-1 x C^-2
b) kg x m^2 x s^-2 x C^-1
c) kg x m x s^-2 x C^-1
d) C x s^-1
e) N x C^-1

I believe it is E but i wondering if there is somthing I am missing. This is how I came up with that answer

E = kq/r^2

E = Nm^2/C^2 x C / m^2
= Nm^2 x C / C^2 x m^2

It says to use base units so for Newton am i suppose to incorporate a kg? I know that the unit for E is N/C but this problem just seems like it would be too easy if that was the answer

Right; your answer of E is correct but I believe there is another correct answer. Think about what a Newton is in terms of other units.

 

[baba89]

Your response:

You are correct in your approach to using base units to determine the units of electric field, E. In this case, the units of electric field can be expressed as N/C, which can also be written as kg x m x s^-2 x C^-1. This is because the unit of force, N (Newton), can be broken down into its base units of kg (kilogram), m (meter), and s (second), while the unit of electric charge, C (Coulomb), is already a base unit. Therefore, the correct answer is option c) kg x m x s^-2 x C^-1.