Energy, Frequency, Wavelength And The Electromagnetic Spectrum printable pdf download

Energy, Frequency, Wavelength And The Electromagnetic Spectrum

Energy, Frequency, Wavelength and the Electromagnetic Spectrum

The light from a heated element is made of several different colors all mixed together. A spectroscope

separates these colors. Some spectroscopes use a prism to separate the colors and some use a diffraction grating.

A diffraction grating is a piece of glass or plastic with thousands of lines marked on it. Because the light goes into

the spectroscope through narrow lines, it is bent into its constituent wavelengths. The set of lines produced by a

heated element is called its spectrum. In this activity, you will use a spectroscope to view some different spectra

and to investigate the nature of light.

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Using colored pencils, fill in the spectra observed for any three different substances.

Spectrum source

Each spectral line represents a photon of electromagnetic energy emitted as electrons fall from excited states

back to their ground states. Most of what we know about electrons comes from the study of light.

We are able to see these photons as spectral lines because their energy falls in the part of the electromagnetic

spectrum that we know as visible light. The spectroscope contains two scales for measurement. The top scale

indicates the energy of the photon in electron volts (eV), while the bottom scale indicates the wavelength of the

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photon in nanometers (1 nm = 1x10

m). To continue our investigation of light, we will use the emission

spectrum for helium, which is shown below.

Energy, Frequency, Wavelength And The Electromagnetic Spectrum