IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Math => Topic started by: superduper2009 on May 24, 2010, 06:22:41 pm

Title: paper 3 help!!!!
Post by: superduper2009 on May 24, 2010, 06:22:41 pm

hello every1..i keep getting confused in questions regarding gradient and y intercept...
how do i do them..
for example paper 31 in 2007 november... q 1 (e) please help me out fast :D

Title: Re: paper 3 help!!!!
Post by: coco pops on May 24, 2010, 06:30:05 pm

V=(row*I*L)/A+k
put this into y=mx+c
V=y 
L/A=x
(row*I)=m
 
so as u have found the gradient from the graph.. put that into (row*I)=m ..u wil find I

then by using this I value put it into the 1st equation ( V= (row*I*L)/A + k
and you wil find k

hope it helps

Title: Re: paper 3 help!!!!
Post by: Asamy111 on May 24, 2010, 06:31:22 pm

hiii .. u just do it as y=mx+c >> c= k and m = lI ( resistivity * I) .. this is wt i kno really .. just wnted to help u

Title: Re: paper 3 help!!!!
Post by: superduper2009 on May 24, 2010, 06:33:09 pm

k thanks alot :D

Title: Re: paper 3 help!!!!
Post by: Aodian on May 24, 2010, 06:48:39 pm

just use the y=mx+c

to find gradient use

m= y2-y1/x2-x1

for example y2=10 y1=4 so   y2-y1=6..

and the same thing goes for the x..

C the y-intercept.. I usually just see where it cuts the Y-axis.. but if you can find the equation of the line then you should be able to find the y-intercept.

y-y1=m(x-x1) equation to find a line.. I like using this one.. Hope it helped