An x-ray tube emits x-rays with a wavelength of 1.0 x 10^-11 m. determine the energy, in electron volts, possessed by the incident electrons

Explanation:

The energy of the incident electron is equal to the energy acquired by the X-rays photon emitted by the tube, which is given by

where

h is the Planck constant

c is the speed of light

is the wavelength

In this problem, the wavelength of the photon is

Therefore, the energy is

And keeping in mind that

We find the energy in electron volts:

a coal burning power plant

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.