The Visible Spectrum Light and its Components Different

The Visible Spectrum

Light and its Components Different colours of light correspond to different wavelengths. White light can be split into different colours using a triangular prism.

ROY G BIV White light Prism Red – longest λ Orange Yellow Green Blue Indigo Violet – shortest λ

Red has the longest wavelength, and so refracts (bends) the least. Green has a shorter wavelength and so refracts more. Blue has an even shorter wavelength and refracts even more.

Click on the picture above for a video on Isaac Newton and the prism.

Line Spectra Each element of the periodic table emits own set of wavelengths of visible light when in gas form. These are called emission lines and produce what is called a line spectrum. The different lines tell us which atoms are present in the gas. This can be useful when astronomers look at the light from stars to see what elements they are made of.

Continuous Spectrum

A line absorption spectrum consists of a complete (continuous) spectrum with certain colours missing which appear as black lines in the spectrum. A line emission spectrum consists of lines of light of distinct colours rather than a continuous spectrum. Now, colour in the diagrams in your workbook.

Experimental Work Use a spectroscope to look at white light coming through the window, then try to see the spectral patterns from different light sources.

Click on the picture above for a video about the universe and spectra.