Physics

[chainfire]

I was give some homework today to find out how to measure the wavelength and intensity of a lamp, using if at all possible (but if not possible, still find out without) a LDR (light dependent resistor). Does anyone know how I can do this? I'm guessing you can measure the change of intensity using a LDR, but other than that, I'm flummoxed. Thanks in advance

[fo3nix]

the LDR will enable you to measure the change in current, giving you a change in power. you can find the power output of the lamp this way, and then you remember that E=hc/wavelength, so can find the wavelength that way.

At least, that's how I'd probably attempt it.

[gen2]

How about passing the light from thelamp through a slit, a condenser lens and a prism (eg, use a raybox). Use the LDR to find the angle of maximum light intensity. Use the refractive index of the glass and the angles of the glass to calculate the wavelength. If the RI of the glass is unknown, you will need a reference beam to calculate that first.

[chainfire]

Thank you for both answers. Just wondering, is there a piece of equipment (that you might find in the school) that can out the wavelength