A laser with wavelength of 632.8 nm is used to excite a gas of atoms which are moving atom that is moving away from the laser at 1.2 * 10⁶ m/s.What is the wavelength of the radiation that these atoms strongly absorb?

Question

Quizplus · Accepted Answer

The correct answer involves understanding the Doppler effect, which describes how the observed frequency (and thus wavelength) of a wave changes due to the motion of the source or observer. In this case, since the atoms are moving away from the source of the laser light, they would observe the light to be red-shifted, meaning its wavelength would be longer than the emitted wavelength. Therefore, the wavelength of the radiation that these atoms strongly absorb would be longer than the original 632.8 nm, making 635.3 nm the correct choice.

A Laser with Wavelength of 632