An X-ray tube operates at 40 kV. Suppose the electron converts 70% of its energy into a photon at each collision. Find the lowest three wavelengths emitted from the tube. Neglect the energy imparted to the atom with which the electron collides.

Explanation

To solve the problem, we will follow these steps:

### Step 1: Calculate the energy of the electrons
The X-ray tube operates at a voltage of 40 kV. The energy (E) of the electrons can be calculated using the formula:
\[ E = eV \]
where \( e \) is the charge of the electron (approximately \( 1.6 \times 10^{-19} \) coulombs) and \( V \) is the voltage in volts.

Given:
...