*Main ideas in bold[/B]
Investigation of the inverse square law of light radiated from a light bulb. (done method, diagram, results and graph)
Independent variable = the distance from the LDR (cm)
Dependent Variable = resistance (k/ohms)
Brief method: using an LDR, bulb, power supply and a resistance metre, get a range of results of the resistance by moving the bulb closer and closer to the LDR e.g. I did first reading 2cm from LDR and then went up by 2cm each time to 20cm. Then plot results on a graph and use it to verify the theory p=k/[d].
The Graph is nearly a straight line positive correlation where it sort of curves in the positive direction from 2-6cm/20cm, then is pretty much linear, not sure if this is how its meant to be.
The main issue I have is how to find (k), the constant and how to use my results and graph to verify the theory.
ps. that method isn't my original I just tried to summarise as it would have been long
Theory being p=k/[d] where: p= intensity d=distance between the LDR and the bulb and k= constant
Inverse square law - I ∝ 1/[d]
The Attempt at a Solution
To be honest I haven't done this kind of practical in a long time due to it being the first one of the year so I don't know where to start but i think I need some help with the first step or 2 and I'll remember.