physics p6 doubts

[aliiiiiiiiii]

people if you have any doubts just post them here any time

 

[ThatReallyReallyWeirdDude]

My only doubt concerns the improving of experiments and such.
Increasing accuracy, reliability etc. :|
But I'm not too worried, I'm great with the rest and that's only a few marks, and even then I can usually score them

 

[aliiiiiiiiii]

My only doubt concerns the improving of experiments and such.
Increasing accuracy, reliability etc. :|
But I'm not too worried, I'm great with the rest and that's only a few marks, and even then I can usually score them

the most used ways like
repeat the experiment several times
in the oscillations u can write take an average time for more oscillations(20) it came yesterday

 

[ThatReallyReallyWeirdDude]

Yeah
for experiments concerning heat, there's insulation(lagging), stirring...

 

[aliiiiiiiiii]

heat u have 2 keep roomtemp constant same temp for all experiments if there is more than 1
stirring??u probably will need 2 write crushed pieces

 

[mrnt3250]

Let's fully discuss this paper right here, so we could improve our overall physics marks since paper 3 (32) was not good.
I'll be posting important notes on experiments soon. You guys also contribute.

 

[tribianni]

heyy i dunnoe anythng like how to draw a metre rule on the pivot thngy such as Q5 http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s09_qp_6.pdf plzz help

 

[mrnt3250]

heyy i dunnoe anythng like how to draw a metre rule on the pivot thngy such as Q5 http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s09_qp_6.pdf plzz help

It clearly says in the question that the rule didn't balance on 50 cm, so we can understand that the meter rule is 100cm and he used its middle value to balance it. But the question also says that it balanced on 49.7cm it means a bit to the left. So to draw it, just scale it down, make 100cm, 10 cm.
Take 4.9 cm from the pivot to the left and draw a line, then from the right side of pivot, take 5.1 cm and draw a line. That's it!

 

[aliiiiiiiiii]

Notes on the Alternative to Practical Paper
1. The preparation for students is a well-designed practical course.
2. 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.
3. Students should understand why the choice of range for the measuring scale should match the
size of the quantity being measured.
4. 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.
5. 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
6. 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.
7. 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.
7. Students should be trained to give a conclusion to an experiment.
8. 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
hope this helps

 

[IGCSE1234]

does anyone know how to find the gradient of a line using the triangle method?

 

[IGCSE1234]

urgent plz

 

[aliiiiiiiiii]

for the graphs
1. label ur axis
2. if the question says to 'draw a straight line graph' then draw a 'line of best fit', otherwise do a free hand curve.
3. when plotting the points, draw 'x' or a dot with a circle around it, i just prefer an 'x'.
4. PLZ MAKE SURE UR PENCIL IS WELL SHARPENED

 

[aliiiiiiiiii]

urgent plz

can u give me the ppr and the Q !!!!!

 

[IGCSE1234]

625 october november 2002 question3

 

[IGCSE1234]

paper 6 aiii

 

[IGCSE1234]

no need thnx i got it

 

[mrnt3250]

I haven't made this, but just found it.
(I'm doing a similar thing, and it will be ready by tonight.)

 

[mrnt3250]

http://www.freewebs.com/faisalj/igcsephysics0625.htm

 

[mrnt3250]

no need thnx i got it

Just get to points on the line, and use the formula y2-y1/x2-x1 to find the graph.

 

[aliiiiiiiiii]

no need thnx i got it

ya thats normal gradiant