Edexcel PHYSICS Doubts

[NightHawkerr]

May 2010 Q 2,
The one where they ask about the intensity of light and distance, and you change the distance from a lamp.
Which one of the following is the measured independent variable? Ans is DISTANCE.
Arent we the ones changing it? So it should be dependent :s
& the next question which of the following is dependent, Ans is Resistance of LDR.. Why?

[Malak]

May 2010 Q 2,
The one where they ask about the intensity of light and distance, and you change the distance from a lamp.
Which one of the following is the measured independent variable? Ans is DISTANCE.
Arent we the ones changing it? So it should be dependent :s
& the next question which of the following is dependent, Ans is Resistance of LDR.. Why?

Independent is the one WE change..and we are chaning the distance so its independent
Dependent is the one which depends on the variable we change
So it resistance of LDR

[Malak]

Questions:

Q1 a from 2010 May
Q1 fro 2011

Q4 from Jan 2010

and

Attachment..

Justify the choice of meter rule?

thx

[MasterMath]

Anyone could help finding the uncertainty? I dont seem to understand how .. You have 4 values ..0.20, 0.18, 0.19 and 0.08 s. you ignore the 0.08 cause its really off.. so you get a mean value of 0.19.. How do you find the uncertainty from here  ?

[The Golden Girl =D]

Anyone could help finding the uncertainty? I dont seem to understand how .. You have 4 values ..0.20, 0.18, 0.19 and 0.08 s. you ignore the 0.08 cause its really off.. so you get a mean value of 0.19.. How do you find the uncertainty from here  ?

can you tell me which paper is that ?

[The Golden Girl =D]

Questions:

Q1 a from 2010 May
Q1 fro 2011

Q4 from Jan 2010

and

Justify the choice of meter rule?

thx

May '10 Q.1]

first of all find total resistance = 100 + 10 = 110 ohms

then calculate the current using formula I = V/R = 3v / 110 ohms = 0.0272 

multiply it by 1000 , you'll get 200 mA  hence answer is C

Jan '11 Q.1]

same as above .. total resistance = 110 ohms  , V = 3 , I = 3/110 = 0.0273 A   

then find V across R {100 ohms } ....V = 0.027 * 100 = 2.7v

hence the one that BEST fits is B that is the 20v


y a meter rule is used?

longer length so measurement to nearest mm appropriate .... 

I believe the answer or the meaning is that because it's more accurate.

[MasterMath]

can you tell me which paper is that ?

2010 MAY 5c)

[The Golden Girl =D]

2010 MAY 5c)

uncertainty = (0.20 - 0.18)/2 = +- 0.01

hence answer is 0.01


to calculate any uncertainty you should do as follows ;

[Max - Min]/2 


they didn't ask for percentage which is why i DIDN'T MULTIPLY IT BY 100

[The Golden Girl =D]

Q4 from Jan 2010

My QP is pretty mess so I'll just describe the experiment.

place a meter rule and a stand right next to it with a pointer
and make sure the meter rule is vertical using set squares
Measure the mass of the ball using top pan balance
drop the ball from a known height say 1.5 m it's just an example By the way
then when the ball bounces back since the reading is not accurate much *difficult to get the exact reading of it's height* we drop the ball about 10 times and take average height of when the ball bounces back [h₂].
initial K.E = G.P.E
% = (mgh₁ -mgh₂ ) / 100

Precaution ; make measurements of height at eye level.

[NightHawkerr]

Can anyone give me the link for AS Physics 6pH07 2011 Jan past paper? Thankyou

[Malak]

Can anyone give me the link for AS Physics 6pH07 2011 Jan past paper? Thankyou

here

https://studentforums.biz/pastpapers/edexcel-january-2011-examiners-reports-%28physics-chemistry-biology-maths%29/

^^ GG
why do you multiply by 1000 for 2010 Q1:S

[The Golden Girl =D]

^^ GG
why do you multiply by 1000 for 2010 Q1:S

Because I want to know the answer in terms of Milli-Ammeter to find out whether any of the answers in millimeter actually are suitable for it or not.

GG

[mustafa09]

Do we have to know how to calculate internal resistance in the unit 3B, if yes can someone tell me how

[Malak]

2009 May 3B ... 6 c) anyone ? thanks in advance!

If you have done part b then ur answer should come out as 14.7 Gpa

1 G = 10⁹

So therefore yes it is consistent as 14.7 GPa = 1.47 x 10 ¹⁰ Pa

[MasterMath]

2009 June 7 a) I get the question but in the MS they said "comment on liquid level" what do they mean :O ?