P.H.Y.S.I.C.S P2 D.O.U.B.T.S CIE

[nid404]

the ms says its a curve :S

-___-

Wait for A.F 

[aloha32]

Hi  there

I need help with the June 09 paper 2 part 1 question 5 b.I don't understand how we get 2 minimas.Can anyone help plz?

thanks !

[halosh92]

i have  a question
to calculate the power dissipated, in a series circuit and in a parallel circuit what do we do
do we just add up the powers?

[nid404]

didn't get you.

give an example?

[halosh92]

didn't get you.

give an example?

like if we have a circuit with two loops
first loop contains 2 resistors
and second loop contains 1 resistor
each has powers of 2W
how do we calculate the total power......for only the 1st loop
and the total power  for the whole circuit.

[Meticulous]

Yes you add up the powers.

[halosh92]

2003 june 2003
Q3bi
i know its length= thita * radius
but why do we add SIN to the thita 

[Meticulous]

halosh..please post the q paper. or its link. for the 17000 time i do edexcel..lol

[halosh92]

halosh..please post the q paper. or its link. for the 17000 time i do edexcel..lol

hahahahah i did no THAT
there u go

[*Hope*]

2003 june 2003
Q3bi
i know its length= thita * radius
but why do we add SIN to the thita 

actually if u notice that a right angle triangle can be formed from the those two lines
the radius is 3\2 which is equal to 1.5
this will be the hyp of a right angle triangle
so the angle 6.5 can be used to find the opp of the triangle which will be the extension
so sin6.5*1.5 will be the extension(opp)

[halosh92]

actually if u notice that a right angle triangle can be formed from the those two lines
the radius is 3\2 which is equal to 1.5
this will be the hyp of a right angle triangle
so the angle 6.5 can be used to find the opp of the triangle which will be the extension
so sin6.5*1.5 will be the extension(opp)

thx...  my head would break if something like this comes in the exam..how the hell r we supposed to think of this 

[zxcvbnm]

x=yD/a
where x is the fringe separation, y is the wavelength, D is distance between slits and screen and a is slit separation.
please explain the effects on intensity of changing y,D and a....for y and D, i know that the intensity changes, but for a, the intensity remains the same....why is that?

[*Hope*]

thx...  my head would break if something like this comes in the exam..how the hell r we supposed to think of this 

haha..I know!! I got it as a quiz once!! And omg!!! I just stoppped thinking!!lool!! But insA no worries hopefully nothing will come like this in the exam

[halosh92]

yes exactly nshalla we should pray 

same paper another question
Q5ai
its not a straight line so shouldnt we draw a tangent here?
and could u explain Q4b

[*Hope*]

yes exactly nshalla we should pray 

same paper another question
Q5ai
its not a straight line so shouldnt we draw a tangent here?
and could u explain Q4b

q5ai: u actually find the exact point and sub in the equation R=V/I
simply at 6v, the current is 40mA but u have to convert it to Amperes so 40*10^-3
the final ans is 150

4b: for i1...it is just guessing but as the ms said: 0.3mm to 3mm

i2 the general formula is x=Dh/a

bii1: as x is the seperation. if u double the D in the eq, the x will double so the separation increases
maximum brightness will be less cuz u r increasing the distance of the light to the screen so there will be less light reaching and so less max brightness

bii2: again as h is increased so if u sub in the eq , the x will increase
the max brightness will decrese..am not sure though of the reason..but as the h increases the frequency decreases so as intensity is A^2 or f^2, the intensity will decrease

bii3:as all r kept constant the x will remain constant which is the seperation
the maximum brightness increases as the intensity increases

Hope i helped and was clear...