2.48 x 10-3 eV

What would be the rest mass of a particle with that energy (in kg units)?

To calculate the rest mass of a particle with an energy of 2.48 x 10^-3 eV, we can use Einstein's famous equation:

E = mc^2

Where:
E is the energy of the particle,
m is the rest mass of the particle, and
c is the speed of light in a vacuum, which is approximately 3 x 10^8 m/s.

First, we need to convert the energy from electron volts (eV) to joules (J) because the rest mass is typically expressed in kilograms (kg) and Joules.

1 eV = 1.602 x 10^-19 J

So, to convert 2.48 x 10^-3 eV to joules:

Energy in joules = (2.48 x 10^-3) * (1.602 x 10^-19)

Once we have the energy in joules, we can rearrange the equation to solve for the rest mass (m):

m = E / c^2

Now, we can substitute the energy we calculated and the speed of light into the equation to find the rest mass.