Light bulbs investigation Light bulbs investigation Practical activity NViz Music Power 3 Gig energy SS1 Light bulbs investigation Light bulbs investigation Light bulbs investigation These bulbs all work from a 12 V supply. They all are ‘rated’ at about 20 W. Your task is to compare their energy transfer efficiency These bulbs all work from a 12 V supply. They all are ‘rated’ at about 20 W. Your task is to compare their energy transfer efficiency PRACTICAL Hints Use the SEP Energy meter (or an ammeter/voltmeter/stopclock combination). Connect a lab pack [set to 12 V] to the input side of the Energy meter. Connect light bulb to the output side of the Energy meter. Press the reset button. Switch on the light, then press start, and record the total energy transferred in 60 seconds while the light is on. Record: current, potential difference (voltage) from the Energy meter and the reading on the ‘light meter’. Copy and fill in the table and compare the size of the energy transfers. PRACTICAL Hints Use the SEP Energy meter (or an ammeter/voltmeter/stopclock combination). Connect a lab pack [set to 12 V] to the input side of the Energy meter. Connect light bulb to the output side of the Energy meter. Press the reset button. Switch on the light, then press start, and record the total energy transferred in 60 seconds while the light is on. Record: current, potential difference (voltage) from the Energy meter and the reading on the ‘light meter’. Copy and fill in the table and compare the size of the energy transfers. To compare the light output of the lamps, use either a light meter OR a PV cell connected to a voltmeter. This gives a reading that is a measure of the brightness of the light bulb. To compare the light output of the lamps, use either a light meter OR a PV cell connected to a voltmeter. This gives a reading that is a measure of the brightness of the light bulb. Light Current (A) Pot. dif. (V) Joules in 1 min Light meter reading Filament lamp Halogen lamp LED lamp Light Current (A) Pot. dif. (V) Joules in 1 min Light meter reading Filament lamp Halogen lamp LED lamp Bulbs can get hot Bulbs can get hot Activity from the nViz unit © upd8 wikid, built by cracking science 2009 This page may have been changed from the original 1