Replace the laser with the LED which is a source of white light. Remove the neutral filter. Direct the radiation of the LED straight at the photodetector. Set the resistance of the resistor to approximately 10 kΩ. Write down the value of the resistance at which you have taken your measurements.
3.1 Measure the dependence of the light intensity on the number of filters for all types of filters provided (gray, yellow and blue). Draw graphs of these dependencies in the same scale as in Part 2.
3.2 Verify whether the formula obtained in paragraph 2.1 is fulfilled for the white light source. Specify a main cause leading to possible violations of that relation.
3.3 Measure the transmittance for pairs of different filters: gray + blue, gray + yellow; blue + yellow. Using the data obtained in the whole experiment, verify whether the transmittance of a pair of filters is equal to the product of the transmittances of each filter.