Some sources radiate light with a continuous range, at others it is line. Even at two sources which colors seem absolutely identical the ranges can look absolutely differently. The device called a spectroscope is intended for their observation.
Instruction
1. Take a big cardboard box. In its sidewall cut through a vertical crack height in several centimeters and from 3 to 5 millimeters wide. It will give to light stream the form of the thin strip stretching in the vertical plane.
2. On an opposite wall of a box place a clean CD-R compact disk.
3. Now in a sidewall of a box cut through an opening under a tube for observations range. In spite of the fact that the tube has round section, the opening has to be oval that it could be turned in the horizontal plane.
4. Insert a tube into an opening.
5. Direct a crack to a light source.
6. Glance in a tube, and, turning it, find a range and consider it.
7. Try to observe by means of spectroscope ranges of various light sources: sun, glow lamps, fluorescent lamp, candle, light-emitting diodes of different flowers. Formulate their difference from each other and try to find information on the principles of work of these light sources in textbooks and the Internet.
8. The ranges received by means of a spectroscope can be photographed the webcam, the digital camera and the mobile phone. You will be able to place the received pictures in reports on performance of school laboratory works or just to use as a part of, for example, collages or wall newspapers.
9. If desired, the intensity of any given line of a range can be measured. Make the primitive photometer consisting of the photoresistor and a multimeter working in the ohmmeter mode. Having darkened the sensor, try to focus on it a lens any given lines of a range. You watch instrument readings: the photoresistor resistance is less, the more brightly it is lit.
10. Now, having obtained data on intensity of lines of a range, it is possible to construct on paper the corresponding schedule (across - wavelength, across - intensity). As our photometer not otgraduirovan, intensity will be expressed in conventional units. And here wavelength with a sufficient accuracy can be measured by eye - on color: 690 nanometers - dark red; 635 nanometers - red; 620 nanometers - red-orange; 600 nanometers - orange; 580 nanometers - yellow; 590 nanometers - lime; 550 nanometers - green; 520 nanometers - emerald; 480 nanometers - blue; 420 nanometers - violet.