Physics paper 6 2012 + chemistry paper 2 2012 discussions

[IGCSE1234]

hi everyone this is for paper 6 physics so again if u have any questions just ask and paper 6 will be discussed here!!!after that chemistry paper 2 will be discussed here too instead of waste of threads!Ammmmmmmmmmmaaaaaazing notes are here too for physics and chemistry?/@!

 

[IGCSE1234]

i will take a day and a half for physics paper 6 and a day and a half for chemistry what will u all do?

 

[IGCSE1234]

Papers 5 and 6 Tips:
You will take one of these papers that test practical Physics. There are some particular points
that are relevant to answering the questions here.
• When plotting a graph it is important to choose the scales so that the plots occupy more
than half of the graph grid. Careless, rushed graph plotting can lose several marks. You
should always use a sharp pencil and plot small, neat, accurately placed crosses. Then
draw a neat thin best-fit line.
• You should understand that if y is proportional to x then the graph will be a straight line
through the origin.
• Diagrams should be drawn with care using a sharp pencil.
• It is important to be able to set up a circuit from a diagram, draw a circuit diagram of a
circuit already set up and also to draw a circuit diagram from a written description.
• You need to know that to read the current through a component (e.g. a lamp or a resistor)
and the voltage across it, the ammeter is placed in series with the component but the
voltmeter must be connected in parallel with the component.
• Column headings in tables of readings must be headed with the quantity and unit as in
these examples: I/A, or t/s, or y/m. Graph axes are labelled in the same way.
• Final answers should be given to 2 or 3 significant figures.
• When carrying out practical work there are usually measurements that are in some way
difficult to take in spite of taking great care. You should comment about these difficulties
when asked about precautions taken to improve accuracy.
• You should understand that the control of variables is an important aspect of practical
work. You should be able to comment on the control of variables in a particular
experiment.
• You should understand the significance of wording such as ‘within the limits of
experimental accuracy’.
• If you are asked to justify a statement that you have made it must be justified by
reference to the readings. A theoretical justification in a practical test will not gain marks

 

[hredoymohammad]

in the chem p 6 xm;s i joined two points on graph by scale? will marks be deducted?

 

[IGCSE1234]

These are some great notes really great :
Notes on the Alternative to Practical Paper
1. This paper is an alternative to a practical exam, not an alternative to a practical course.
2. The preparation for students is a well-designed practical course.
3. The course should teach candidates how to make measurements using many different types of
instruments. They should see the instruments, handle them, discuss their scales and the scale
units before using the instruments.
4. Students should understand why the choice of range for the measuring scale should match the
size of the quantity being measured.
5. Students should know how to record measurements in a table. A table should record all the
measurements needed to obtain the value of a given physical quantity. For example if a length l
is derived from l = l2 - l1 then l1 and l2 should appear in the table. Columns (or rows) in the table
should be headed with the name of symbol of the physical quantity. The unit in which the
quantity is measured should be included. The SI method is recommended. Encourage neat work.
6. Ideally, when performing an experiment (and relevant readings are recorded) it is helpful to
arrange the experiment so that one variable is increased step by step. Candidates should always
look for a trend in the recorded results. Some trends are
 y increases as x increases
 straight line through the origin, if x is doubled then y is doubled, direct proportionality
 y decreases as x increases
 x times y = k, inversely proportionality. Inverse proportionality is generally not properly
understood
7. A graph is the best way to display the results of an experiment.
 y/unit against x/unit should be understood as the label of each axis
 axes should
 be labelled with quantity, unit and scaled
 as large as possible, but should not use an awkward scale to achieve the size
 plotting should be neat and as accurate as possible
 graph lines should be neat, thin and a good fit (if there is scatter of points they should lie
either side of the line{in a rough way!! }). Straight lines should FILL the page (even beyond
the range of points) so that any gradient calculation can use the largest y and x. Students
should understand why! (y is a measurement.)
 students should describe what information is obtained from a graph, see note 6.
8. Students should understand the idea of a fair test or comparison in which only one variable is
altered at a time, eg when investigating how rate of cooling experiment depends on temperature
room to be kept constant--room draughts, volume and type of liquid, amount of stirring.
9. Students should be trained to give a conclusion to an experiment.
10. Good procedures: -
 repeat readings to spot anomalous errors or to calculate an average
 avoid making parallax errors, {the line of sight should be perpendicular to the reading on the
scale}
 look carefully at any scale that is used eg
 notice the unit in which the scale is calibrated - always give the unit of any measurement
 notice the maximum reading that can be obtained
 notice the smallest change in value that can be obtained
 aim to use quantities that have magnitudes that are towards the upper values of the scale in experiments involving the measurement of a length
 try to use lengths that are at least 100 mm in length
 you can measure to the nearest mm with a rule, or perhaps 0.5 mm
 when measuring heights ensure that the rule is held perpendicular to the base
 know how to arrange apparatus so that it is parallel or perpendicular to a bench
 know how to arrange a set square either side of a cylinder/sphere to measure diameter
 in light experiments using objects, lenses and a screen
 ensure that each item is aligned so that the centre of each item is at the same height and
on the same horizontal straight line (ideally use the term optic axis)
 use a fiducial aid when measuring a length, eg mark the middle of the lens on the bench
 try to use a translucent screen
 perform the experiment in a shaded part of the laboratory
 in ray tracing experiments
 when using marker pins space the pins so that they are at least 60 mm apart
 ensure that the pins are vertical
 draw neat thin lines
 use the largest angles available and draw the arms of the angle longer than the radius of
any protractor being used, ie a large radius is desirable
 when using a thermometer
 position the eye so that the mercury thread appears to touch the scale
 decide whether you can read between the marks on the thermometer, ie some
thermometers can be read to better than 1 ºC even though the marks are every º C
 check whether the thermometer is full or 1/3 immersion
 in heat experiments
 choose volume/mass values of the quantities that give large changes in the temperature
 insulate the container, cover the container
 stir and wait for highest temperature after stopping heating
 in electrical experiments
 check for a zero error
 tap the meter to avoid sticking
 initially choose the highest range for the ammeter/voltmeter, then reduce the range for the
ammeter so that the deflection is almost full scale
 always check polarities before closing the switch (completing the circuit)
 always check that connections are clean.
 switch off the current when not making a measurement.
 when measuring resistance use low currents/voltages to avoid heating and changing the
resistance you are measuring
 when measuring an interval of time
 a stopwatch can measure to about 0.1 s, although it may give a reading to 0.01 s
 for oscillations (of a pendulum or vibrating rule), be able to define a complete oscillation
 time N oscillations, usually N>10 and use the terminology periodic time T = t/N
 explain how to use a fiducial aid at the centre of the oscillation
 explain where the eye should be placed to avoid parallax errors

 

[IGCSE1234]

in the chem p 6 xm;s i joined two points on graph by scale? will marks be deducted?

i don't think so

 

[IGCSE1234]

 

[IGCSE1234]

Physics laboratory safety precautions / rules:

* Live wires should not be touched.

* Hot Objects should not be touched with barren hands instead of that gloves should be used the most common process is heating of water in thermodynamic experiments.

* Circuit connections should be checked and approved by the teacher and then only the circuit should be switched ON.

* While changing components of the circuit the power should be switched so that one should not experience electric shocks.

* Safety spectacles, gloves and other safety components should be used while handling experiments.

* While handling a mercury thermometer one should take of the mercury spills.

* No other laboratory instruments should be touched or handled which is not involved in the course of experiments.

micrometer : can measure the thickness of any small thing to 0.01 mm
vernier : can measure the inner and outer wall of anything to 1.05mm
Control Variables
Precautions
Units ( eg.. voltage is V etc. ) cause the units hold 1 mark of the question
Statements & justification
The rest are calculations and measurements
To produce more accurate or reliable results:
• Repeat experiment, to calculate average reading.
• Avoiding parallax error, look perpendicular to the ruler.
• If accuracy in measurement was asked, check for zero error.
Improvements that could be done to the experiment (temp. cooling):
• Same initial temperature.
• Same volume of water.
• Same shape of beaker.
• Beakers of same surface.
• Same room temperature.
• Stirring the water in the beakers.
• Same time intervals.
• Same surface area. (Unless given different containers)
• Adding water or cooling effect at regular intervals.
Heat loss could be reduced by:
• Insulation of beaker.
• Covering beaker with a lid.
For 2 values to be directly proportional,
• The graph of the values must be a straight line from the origin.
• As value 1 increase, value 2 increases.

For images produced from lenses on screens, precautions taken:
• Use of a darkened room for the experiment.
• Avoiding parallax error in measurement, and look perpendicular to the ruler.
• Object and lens at the same height from bench.
• Object/lens/screen is perpendicular to the bench.
To draw an image created from lens:
• Inverted from the original object.
• Sides are multiplied by the magnification.
*If values have difference by 0.1 or 0.01, that is the limit of experimental accuracy, so answers are about the same.
For spring extension experiment, variables that should be constant in the experiment:
• Number of coils.
• Diameter of spring.
• Selection of loads.
• Mass of spring.
http://www.opamp-electronics.com/tutorials/experiments_ch_003.htm

for improving the accuracy of the results (for experiments):
Minimizing heating effect of a current:
• Lower current
• Increase 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

Periodic time (T) is measured by timing a number of oscillations, then divide the time taken for all the oscillations by the number of oscillations

 

[IGCSE1234]

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 string method
• Avoid parallax error
• Repeats and average
• Thinner string
• Parallel winding of springs
It's not the BEST list in the world, but hopefully it will help...
Control Variables
Precautions
Units ( eg.. voltage is V etc. ) cause the units hold 1 mark of the question
Statements & justification
The rest are calculations and measurements which are easy.. they provide the equation in the question

 

[IGCSE1234]

really helpful learn and understand then go get a full mark!!!

 

[IGCSE1234]

i really hope these resources help u all Wait for more and more and for paper 6 discussion. Then i will start putting chemistry notes paper 2 !

 

[IGCSE1234]

thnx everyone

 

[Z.A.M]

Thesevthings r very useful thank may Allah help u all

 

[Ahmed Abdullah]

Thank u very much, that really helped alot

 

[Z.A.M]

Aren't u guys gonna have chem p 3

 

[white rose]

i really hope these resources help u all Wait for more and more and for paper 6 discussion. Then i will start putting chemistry notes paper 2 !

thanks a lot hope it helps.....

 

[Ahmed Abdullah]

i will have chem paper 3

 

[IGCSE1234]

Aren't u guys gonna have chem p 3

i am core so i only havve p1 p2 p6 no p3 p4 p5

 

[ShOlO]

Wa

in the chem p 6 xm;s i joined two points on graph by scale? will marks be deducted?

Wait , u already did Paper 6 Chem. ?! how was it ?Was it hard !?

 

[ShOlO]

Thanks so much for the notes !