Author Topic: IGCSE physics easy question  (Read 1517 times)

holtadit

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IGCSE physics easy question
« on: December 08, 2009, 02:33:28 pm »
Look at question 9 (c) of the attached paper.

How do they get I^2 R and what formula are they referring to. ?
« Last Edit: December 08, 2009, 02:50:54 pm by Ari Ben Canaan »

holtadit

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Re: IGCSE physics easy question
« Reply #1 on: December 08, 2009, 03:32:08 pm »
HELP!

holtadit

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Re: IGCSE physics easy question
« Reply #2 on: December 08, 2009, 03:35:31 pm »
Also question 9 c ii of the attached paper .

THIS A DIFFERENT QUESTION FROM THE ONE ABOVE

How do u know in which way the flexible wire moves ? I applied flemings left hand rule but i dont know in which way the index finger points... where is the North and South poles ?

Offline astarmathsandphysics

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Re: IGCSE physics easy question
« Reply #3 on: December 08, 2009, 03:36:36 pm »
Half am hour

holtadit

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Re: IGCSE physics easy question
« Reply #4 on: December 08, 2009, 03:41:35 pm »
finally someone decides to help  :)

Offline astarmathsandphysics

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Re: IGCSE physics easy question
« Reply #5 on: December 08, 2009, 03:58:12 pm »
The attacjed file is corrupt. I looked up the question on my version of the paper and it doesnt look the same as yours.

holtadit

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Re: IGCSE physics easy question
« Reply #6 on: December 08, 2009, 04:06:05 pm »
For my first question see paper 3 may june 2008

for the second question see paper 3 november 2008

Offline astarmathsandphysics

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Re: IGCSE physics easy question
« Reply #7 on: December 08, 2009, 04:16:00 pm »
P=IV but Y=IR so P=I(IR)=I^2R

Offline astarmathsandphysics

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Re: IGCSE physics easy question
« Reply #8 on: December 08, 2009, 04:19:26 pm »
Use the right hand grip tule on the thick wire to find the direction of the field - clockwise and left hand rule on thin wire to find direction of force - towards thick wire. Alternativley you could just use - like currents attract.

holtadit

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Re: IGCSE physics easy question
« Reply #9 on: December 08, 2009, 04:31:57 pm »
for the left hand rule where would the index finger (magnetic field) point ? and why ?

Offline Ghost Of Highbury

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Re: IGCSE physics easy question
« Reply #10 on: December 08, 2009, 04:47:10 pm »
lemme explain it to u ..hold on
divine intervention!

Offline Ghost Of Highbury

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Re: IGCSE physics easy question
« Reply #11 on: December 08, 2009, 04:51:01 pm »
i know the diagram sucks, but try to understand plz..

the middle finger shud point downwards, and the index finger shud point straight...hope u get it.

if not tell me..
divine intervention!

Offline astarmathsandphysics

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Re: IGCSE physics easy question
« Reply #12 on: December 08, 2009, 05:18:49 pm »
Wxactly right