Caluculating how light intensity varies with wavelength?

Question

How can i use an LDR to measure the above? The light source is a lamp

Answer 1

I don't think you can. The intensity of the light is not the same as the wavelength. it is, in fact, a measure of the amplitude. If you want the wavelength, you need a spectrometer of some description. or you might be able to make a crude determination with a prism. There is, I suppose, a correlation between the refractive index and the wavelength- but I don't know what it is without further reading.

Answer 2

to be frank, the answer above is utter nonsense. you can measure the effect, or otherwise why would they set it as this years AS planning excercise??!
basically, you need a lamp that can take a bulb that gives off the same wavelengths of light and the sun.
then to split the wavelengths you need a diffraction grating.
then, since we know that intensity is proportional to 1/Vout, that is what you plot on your graph. 1/Vout on the y-axis and wavelength on the x-axis. hope that this helps, ive just finished mine
good luck