Through what potential difference δv must electrons be accelerated (from rest) so that they will have the same wavelength as an x-ray of wavelength 0.185 nm ?

The De Broglie wavelength of the electron is equal to

where h is the Planck constant and p is the electron's momentum. Since this wavelength must be equal to that of the x-ray,

we can re-arrange the previous equation to find the momentum of the electron:

The kinetic energy of the electron is equal to the square of the momentum divided by twice its mass:

When the electron is accelerated by a potential difference , the energy it gains is

where q is the electron charge. Re-arranging the formula, we find the potential difference:

answer: the direction of the wind is expressed as the direction from which the wind is blowing. for example, easterly winds blow from east to west, while westerly winds blow from west to east.

explanation:

3.2x10^7