qspec.v_e  (  e ,  m ,  v0 = 0 ,  relativistic = True  )[source]

The velocity $v = \begin{cases}c\sqrt{1 - \left[\gamma(v_0) + E / (mc^2)\right]^{-2}}, & \mathrm{True}\\ \sqrt{v_0^2 + 2E / m}, & \mathrm{False}\end{cases}$

Parameters:

earray_like

The energy $E$ added to the kinetic energy of a body with velocity v0 (eV).

marray_like

The mass $m$ of the body (u).

v0array_like

The initial velocity $v_0$ of the body (m/s).

relativisticbool

The calculation is performed either relativistically (True) or classically (False). The default is True.

Returns:

vndarray

The velocity $v$ of a body with mass m and velocity v0 after the addition of the energy e (m/s).