Breckland Scientific 2021 Catalogue

Optics

Properties of Light

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1 LASCELLS PLANCK’S CONSTANT A selection of LEDs cover the range from deep blue to infra-red. By monitoring the voltage at which each LED just begins to emit light, a graph of energy input as a function of light emitted frequency can be plotted and an approximate value of Planck’s constant deduced. The system is an excellent illustration of modern electronics and gives a good investigation into a difficult topic in Post-16 physics. The LEDs are mounted in a self-contained box with voltage control and monitoring points for current and voltage. A protection resistor is included to prevent damage to the LEDs. Complete with viewing tube but requires a 5V d.c. lab. power supply. Cat No. Description Price Per ATQ-305-100 Planck’s Constant 95.82 ea. 2 PLANCK’S CONSTANT APPARATUS This apparatus is designed to determine the approximate value of Planck’s constant, using a range of LED’s of known wavelength, to allow the electron/photon energy to be calculated. There are 7 LED’s, covering the light range from deep blue at 470 nm to near IR at 940 nm, mounted on a box with 4mm sockets for attachment to a voltmeter and ammeter for voltage and current measurements. When each LED begins to emit light, the voltage is measured and a graph of energy input as a function of light emitted frequency can be plotted to deduce the value of Planck’s constant. Requires a 9V d.c. power supply (standard lab power supply). Cat No. Description Price Per ATQ-400-100 Planck’s Constant Apparatus 66.85 ea. 3 DIFFRACTION GLASSES Simple diffraction glasses for seeing light sepa- rated into its constituent parts. Cat No. Description Price Per OPL-050-100 Diffraction Glasses 7.16 10 4 DIFFRACTION GRATINGS SLIDE 3 gratings in a single holder with 100, 300 and 600 lines/mm Size: 90 x 30mm with three 16 x 19mm apertures. Cat No. Description Price Per OPL-150-100 Diffraction Gratings Slide 24.52 ea. 5 DIFFRACTION GRATINGS Mounted in a tough plastic slide frame of 50 x 50mm. Aperture size: 36 X 24mm. Cat No. Description Size Price Per OPL-100-100 Diffraction Gratings 80 lines/mm 14.58 ea. OPL-100-150 Diffraction Gratings 100 lines/mm 14.58 ea. OPL-100-200 Diffraction Gratings 300 lines/mm 14.58 ea. OPL-100-250 Diffraction Gratings 600 lines/mm 20.17 ea. OPL-100-300 Diffraction Gratings 1200 lines/mm 20.17 ea.

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Lascells Planck’s Constant

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Planck’s Constant Apparatus

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Diffraction Glasses

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Diffraction Gratings Slide

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Diffraction Gratings

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