Energy of Electron: Solving Eqn & Variable k

[patapat]

So I'm staring at this equation in my book and I am not sure what the variable k represents in this equation: E=(p$$^{2}$$/2m)-(ke$$^{2}$$/r) and I am assuming e refers to the charge of the electron.

 

[christianjb]

Maybe

k=1/4pi epsilon0

 

[G01]

"K" is the constant in Coloumb's Law, just like "G" is a constant in Newton's Law of Gravity.

Numerically, K has a value around 9X10^9 Nm^2/C^2.

As mentioned above by patapat, K can also be represented as:

$$K=\frac{1}{4\pi\epsilon_0}$$ where $$\epsilon_0$$= 8.85X10^-12 and is called the permittivity of free space, which is a fundamental constant of electromagnetism.

 

[premagg]

some of the books use 'k' for representing the quantity '1/4pi*e₀'