Procedures:
1. The first part of the experiment is to understand the different efficacies of an incandescent lamp and a fluorescent lamp by comparing the luminance measured by a digital luxmeter. The unit of the luminance is lux, and one lux means one lumen per one square meter (1 lux = 1 lm/m2). Connect the ballast/fluorescent lamp circuit as shown in Figure 14. Turn on the main switch K, and you will see the lamp ignited. Wait for at least 1 minute so that the lamp is at its steady state. Record the input power Pin. Use digital luxmeter to measure the luminance of the fluorescent lamp. Keep a constant distance between the lamp and the luxmeter (10cm is recommended) with the photometric probe facing the lamp directly as shown in Figure 15. Slightly adjust the angle between the probe and the lamp to get a maximum reading and record it down. Now turn off the lamp. There is one incandescent lamp setup for comparison. The lamp connection is shown in Figure 16. You can adjust the autotransformer so that the input power as indicated in the wattmeter is the same as which you recorded previously, Pin. Measure the luminance of the incandescent lamp using the same method you used for the fluorescent lamp.