Recent content by ffrog

Homework Statement Does anyone know what's on the 2009 AQA AS level practical paper the ESA one? Homework Equations Any The Attempt at a Solution I don't know any thing but i guess it could have be on mechanics.

oh my god thankyou i didnt know that and that's all i wanted to here that solves my whole problem.

I get that it says a minimum frequency is required and there is a maximum energy required but you have failed to prove this bit which is my hardest

so what you are suggesting is me saying look at the formula it gives you proof? sorry but i am not sure that will fly

what E=hf or do you want the photoelectric equartion and how do either of them prove it fh=workfunction+Ek(max)

Homework Statement When monochromatic light is incident on a metla plate,electrons are emmited only when the frequency of light exceeds a certain frequency. Explain in terms of energy, why this threshold frequency exist and why photon theory of light provides a better explnation of the...

IF pressure drops gas expands if tempreture rises gas expands. So if the tempreture falls propotionaly to the fall in pressure then the gas stays the same volume. However this isn't the case and the pressue falls faster than the tempreture so the gas expands. should help

no lowly pion you are wrong what he needs is the other SUVAT equations namely. S=0.5(u+v)t then rearrange to get V (u is intitial velocity) then you put that into the the kenetic energy equation KE=0.5mv^2 then you have got your anser

dude i gave you the anser to part a) part b) however i now know what you must do you need to use the resistants calulated in part a and then put it into the torque equation

you could just simply do some proofs by just proving the masses have a higher force by simply crunching numbers like 5 times for each side one light on heavy and increase mass for the light one and increas for heavy and show how the force increase and drops. pretty simple but shou8ld prove it

ok simply put you need to do a suvat equation can't rember which one that will work out s and it must contain v then put v=0 and fill in the other numbers then you have your distance as whatever s=

if you are in the Uk get a copy of the sylabus and wave it in his face saying you don't need to know it sorry its my only anser.

ok well first question simple anser they are more stable if they have a complete outer shell of electrons and atoms always want to be in there most stable form. 2.It depend what the solid is. Metalic bonding holds togther soild metals. Basically dipole-dipole, hydrogen bonding and...

ok you will never need to know why its is the case until you do it as a job or do it at uni you do whoever have to recognise the graph odd but true.(Uk only)

the first part is fairly simple. use the equation F=ma so what you do is do get 8.9*0.76=actual F then do 15-Factual=frictional force. however i can not help you with the secound part as i have never done it.