IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => IGCSE/ GCSE => Reference Material => Topic started by: dodi23 on May 10, 2010, 05:47:07 pm
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Minimising heating effect of a current:
• Lower current
• Lower voltage
• Add a lamp
• Increase resistance of a resistor
To increase accuracy of ray diagrams
• View bases of pins since pins may not be vertical
• Keep pins further apart
• Use more pins
• Avoid parallax, explain action and reason
• Repeats and average
Adjustments made to experiments will be made to increase accuracy
Improvement made to experiments about heating effect and insulation
• Lids
• Repeats
• Stirring
• Record max. Temperature
• Add insulation
• Keep constant room temperature
• Avoid heat loss
How to check if a rule is vertical:
• Protractor
• Use of set square
• Plumb line
• Spirit Level
Precautions taken in experiments about formation of images by a lens
• Use a darkened area
• Meter ruler on bench or clamped
• Object and lens same height on bench
• Mark on lens holder to show centre of lens
• Take more readings
• Avoid parallax error, explain action and reason
• Lens\screen perpendicular to bench
Variables in experiments about springs and stretching effect:
• Number of coils
• Length of spring
• Diameter\thickness of spring or wire
• Range of loads
• Length of wire
• Coil spring
Periodic time (T) is measured by timing a number (n) of oscillations, then divide (n) by the time taken.
Drawing graphs:
• Label axis
• Choose a proper scale
• Well judged best fit line
• Thin and neat lines
Measuring the gradient:
• Draw a triangle on graph
• Use clear lines
• Triangle must be larger than half the line
Sources of error in calculating circumference by string method:
• Parallax
• Diagonal winding
• Thickness of string
Improvement made to calculating circumference by sting method
• Avoid parallax error
• Repeats and average
• Thinner string
• Parallel winding of springs
hope this helps... ;)
best of luck!!!
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+rep
awesome:)
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Great work :)
We had someone who posted this last year...but i couldn't find it
Thanks :)
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thx alot !!!! ..god bless u !!! ..
ummm srry but i didn't get the gradient part !! ....my teacher said rise/ run......can u plz explain ur way?
thx in advance
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Great work .. i'll +rep u in an hour .. :)
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nytime ;)
i didnt copy it, i wrote it.
the golden girl:
find two points in the line, connect them in a triagle
then measure
(x1,y1) (x2,y2)
gradient=(y2-y1)\(x2-x1)
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nytime ;)
i didnt copy it, i wrote it.
the golden girl:
find two points in the line, connect them in a triagle
then measure
(x1,y1) (x2,y2)
gradient=(y2-y1)\(x2-x1)
ohh so it's in the mathematical way , k ...now i get it :P ..lol
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All hail queen Dodi23!!!!!!!!!!!!!
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Heey Thanks for that. Many people kept asking for that :D
Hope u make for other papers too :)
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thanksssssssssssssssssssssssssssssssssssssssssssssssssssss
helped alot 8)
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Thanks
+rep ;D
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welcome all :D
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hey for the image formed by lens, is keeping eye perpendicular to scale correct???
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Thanks a lot! +rep
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To increase accuracy of ray diagrams
• Avoid parallax, explain action and reason
How do you explain action, e.g.? For example, in a question they ask: "State and explain the reason for one precaution that you took to gain an accurate result".
How would I explain about parallax?
I know about the other one, say look at bases of pins because they may not be vertical.
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Life saver, thanks ;)
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I dont know if its too late .. but u might wanna add "Spirit Level" in 'How to check if a rule is vertical' .. :)
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I dont know if its too late .. but u might wanna add "Spirit Level" in 'How to check if a rule is vertical' .. :)
Ill add that point. ;)
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Is there gonna be something like this for the Biology paper 6? ;D
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i dont think so :(
i hate bio like hell nd its soo freakin hard
i could hardly study myself :'(
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i dont think so :(
i hate bio like hell nd its soo freakin hard
i could hardly study myself :'(
shufi , itha giltai smthn is hard biykoon hard ....lazim tukuneen mitfa2la , k? ...lana biha6reega tigdireen tidreseen ,wi tisaw3ibeen kilsha o 7eta yitrasa5 fi mi5ich ;)
bitwafeeg inshAllah :D
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Thanks wallah ur always helpful
ill +rep u 4 ur encouragement
By the way where r u from??
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Thanks wallah ur always helpful
ill +rep u 4 ur encouragement
By the way where r u from??
i know how to talk in most arabic accents so i'll be a bit mysterious with ya :P
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i know how to talk in most arabic accents so i'll be a bit mysterious with ya :P
Egypt?
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nope ,I won't tell ya ;)
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shufi , itha giltai smthn is hard biykoon hard ....lazim tukuneen mitfa2la , k? ...lana biha6reega tigdireen tidreseen ,wi tisaw3ibeen kilsha o 7eta yitrasa5 fi mi5ich ;)
bitwafeeg inshAllah :D
Tistaw3ibeeen
:)
Thanks, +rep.
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Tistaw3ibeeen
:)
Thanks, +rep.
Welcome.
Check pm for this xP
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Welcome.
Check pm for this xP
okay :P