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Production of Electromagnetic Waves

X-Rays

Example: An X-Ray machine, such as the one used in a medical office operates by accelerating electrons with a very large potential difference (about 25,000V). These electrons are accelerated into a positively charged plate. As the electrons are very excited and moving very quickly, their impact on the plate results in a large energy release. This energy is released in the form of high energy photons otherwise known as X-Rays. Suppose that a single electron were to release all of its energy among 5 photons how much energy would each photon have?

Draw a picture	Known	Find
	$q_e=-1.6\cdot 10^{-19}$ C $\Delta$ V = 25,000V N=5 photons	Energy per photon

Base Equation $\Delta$ E=( $q_e$ )( $\Delta$ V)
(-1.6 $\cdot 10^{19}$ C)(25,000 V) = 4.0 $\cdot 10^{-15}$ J
Divide the total energy by the number of photons in order to determine the energy per photon
$E_p=\frac{\Delta E}{N}$
$\frac{4.0 \cdot 10^{-15} J}{5 photons} = 8 \cdot 10^{-16} \frac{J}{Photon}$