Recent content by United fan

does anyone know the accuracy and range of the standard voltmetres and ammetres used in schools? as we need to write this too i think

Yeah i was thinking that but its not exactly proportional. to be honest i don't think they exect us to do any complicated calculations and it will be something like wavelength against resistance or current.

Actually i think i just found that that equation is for sound waves. Hmm this is difficult. I really do think it would be simpler to just measure current or resistance and plot it against wavelegth. do any of you guys know what you're going to do for intensity?

Hmmm. So did he say that intensity = 1/resistance? cause i guess that's not to hard to calculate. in my textbook i found that intensity = power/area and froma point sorce it is inversley proportional i.e intensity =1/r squared. I would probably use the first one and then measure the power...

cheers mate.

yep hope so too mate. if your teacher does say its alright to use current, let us know mate otherwise I've got a bit of a problem as the exams on thursday

Well i was working under the idea that if intensity increases the resistance will decrease and so the current will rise or in other words if intensity rises current will rise and so using current as a substitute for intensity seems plausible.i hope it is at the least as that's what I'm planning...

Yeah i was thinking of doing something like that. i will probably measure current and do a graph of wavelegth against current( as current should increase as intensity increases) or wavelegth against resistance.

So what have you guys decided to do for intensity?

alright cheers mate, i'll work on that. I think you can get coloured filters which come with wavelength specifications which would be a lot simpler then diffraction grating i think.

Sorry no idea mate. So with the intensity thing are you going to calculate the power around the LDR using an ammetre and voltmetre when different wavelegths shine on the LDR?

Oh, ok. cheers mate. So do you think i should have one circuit with the LDR and the ammetre and then another one with the lamp and a resistor so that the current doesn't get too high? Thanks for the help

Hi guys. I had similar ideas to some of you. I decided to measure the wavelength using coloured filters, i.e blue, red green etc. However I'm not to sure about how i should set the circuit up. Should i have the LDR in series with the lamp or create a potential divider with the output...