What Are the Correct Units of Coulomb's Constant?

  • Thread starter Thread starter ZedCar
  • Start date Start date
  • Tags Tags
    Constant Units
AI Thread Summary
Coulomb's constant, used in Coulomb's Law, incorporates the permittivity of free space (ε0), which has units of F/m. There is a debate on whether the units of Coulomb's constant should be expressed as F/m or F^-1m. Some argue that since Coulomb's constant (ke) is defined as 1/(4∏ε0), it implies a different unit interpretation. Further clarification reveals that the unit of ε0 can also be expressed in basic SI units as A²s⁴kg⁻¹m⁻³. The discussion emphasizes the complexity of deriving units in electrostatics.
ZedCar
Messages
353
Reaction score
1
Coulomb's constant, which appears in Coulomb's Law, contains ε0.

The units of ε0 being F/m

Are the units of Coulomb's constant therefore F/m ?

Thank you.
 
Physics news on Phys.org
ZedCar said:
Coulomb's constant, which appears in Coulomb's Law, contains ε0.

The units of ε0 being F/m

Are the units of Coulomb's constant therefore F/m ?

Thank you.

I would have thought F-1m since ke = 1/(4∏εo)
 
ZedCar said:
Coulomb's constant, which appears in Coulomb's Law, contains ε0.

The units of ε0 being F/m

Are the units of Coulomb's constant therefore F/m ?

Thank you.

Yes, but farad can be derived from the basic units of the SI system, so the unit of ε0 is A2s4kg-1m-3 in terms of the basic SI units.

ehild
 
PeterO said:
I would have thought F-1m since ke = 1/(4∏εo)

For parallel plate capacitors, C=εA/d (A is the surface of the plates, d is the distance between them) so farad=[ε]m.

ehild
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »

Similar threads

Graphs of RC Circuit Responses
Replies
3
Views
944
Electron moles present in wire cross-section
Replies
7
Views
1K
Electron bound to proton by gravity
Replies
3
Views
1K
Work, energy, power unit (coulombs)
Replies
2
Views
1K
Gauss's Law vs Coulomb's law problem
Replies
3
Views
2K
Coulomb's Law and Conditional Convergent Alternating Harmonic Series
Replies
11
Views
2K
The time for a proton to reach a certain velocity
Replies
4
Views
2K
Electric field of point along the central vertical axis of a triangle
Replies
3
Views
866
How to calculate the Coulomb barrier between a proton and a lithium nucleus
Replies
9
Views
3K
Law of Conservation of Energy Proof
Replies
22
Views
2K

Hot Threads

Recent Insights

Back
Top