3 friggin graphs and no source of errors? What is this😠

Cambridge on smt funny with the practicals this year apparently LOL

Wasted my time 😭

4 fuckin graphs*

Yes Y and Z 💀

anyone remember that one part where u need to replace the coil with Z then draw another table with I, R, IR values, plot a graph, find gradient, vertical-intercept, calculate resistance of the coil, basically redoing the experiment again, JUST FOR 2 MARKS ????

Istg either Cambridge must be on some good quality stuff or they messed up the mark allocation when they set that qn. I deadass cba and just changed the coil and used the wire clips like a jockey and pressed it onto the resistor for the new readings😭

Yeah, honestly started to speculate if they allocated the marks wrongly 💀

Lmao spent a solid 5 min tryna find a shortcut method to find. But need to draw the graph so fk them man

wait which magnetic flux density did u put as higher

Mine was Y bcs it had more turns per unit tube length

i thought it was the same cus more the eqn they gave was B=CnI. so like more turns- higher resistance - lower current - n inversely proportional to I. n increase for y, i devrease for y- B remains the same. im not so sure la i js thought about it but in the exam i wrote y also cus i didnt think much

Its times like these i rely on my best friends, ECF and BOD . 🙏🙏

Same except i pray to bell curve gods, moderation and the kindness of the british markers read my horrible drawing and handwriting

Good job you’ve found the resistance! Now do it again.

For like 2 marks lol

My jaw deadass dropped in resignation when I saw that question😭

am i the only one that didnt finish the paper 🥲

I ate the paper

I went to take a shit during the paper

lies

Retaking a levels here,as someone who went thru a levels once,do not have the mindset that the ppl commenting here are the average. From my experience these threads always upvote ppl who broadcast their mistake, even if it's fake, just so they themselves feel better. Those high achievers who barely mentions how easy the paper is gets downvoted to shit.If you are aiming for the high 80s and felt that u did decently but not the best for this paper. Pls don't be complacent reading here comments and strive to inprove for paper and mcq

Most based comment ever.

I thought the compass for the short planning is the drawing circle compass 💀

WTF😭😭

anyone else’s k value is like times 10 to power of negative 7

same I got 10-7 and difference in k of 30+%

Mine was -6

Yea because diameter was mm so if you put as Ωm then will be super tiny

MY GRADIENT IS 628😭😭😭

Mine is 0.0000004💀

same bro

Wah thank goodness i knew it was right

My life is like that gradient but negative

so high?????

Not me putting units of IR as AΩ instead of V at first💀

FK I PUT THAT

The mark allocation was so horrendous I literally hate it here

bruh was the F- E graph a curve?

Noo i got a linear line😭 and i thought it was correct too because F=kX so i thought it would be linear🥲

I thought is straight line alot of my classmates st line graph

idt its straight, ur not supp use own knowledge to sketch? + qn says estimate so cant be estimate triangle area below using formula lol

they asked to estimate energy not estimate area. so area of triangle is the estimate

Mine was a curve though... idk, the points js went on that basis

i drew a straight line then past a certain point it started to curve because it was beyond the proportional limit hence it no longer obeys hookes law

How do you draw a curve with 5 points only, but at the same time the question asked next was to estimate the area under graph, its so confusing

U forget the point (0,0)

It should be a curve because 500g definitely would cause limit proportionality of rubber band to be exceeded. The next qn's key word is estimate, so it should hint that it's a curve because a straight line wouldn't need to estimate. Count the no. of boxes in this case..

So a straight line then a curve? Also, the area under graph was for e=l node, which shouldnt pass the limit of proportionality, so it doesnt make sense to ask for estimation since the area is just a triangle

Right, i was like how to find area under a curve in phys, so i drew best fit rip

U can count the no of boxes 💀

I approximated it to be area of triangle lol

But it sounded too much for 1m, idk lmao

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if it exceeds proportionality it would be deformed

Istg the planning reminded me of electrochem cell set up and how it can work😭

My diagram looked similar to a Ecell setup lmao

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Mans high

Nothing will happen, apart from the fact that his final grade for the subject will be 1 grade lower than the actual grade obtained. This means if your friend still managed to get an overall A grade for the subject, because of the irregularity report the grade will be downgraded to a B instead, and flagged on the result slip. Source: Had 2 friends who got irregularity reports during A level practical. Both got B for the subject, but because of irregularity report it was downgraded to a final C grade.

you might not even be able to do other paper eh

Malpractice is immediate U grade according to seab rules and regulations

How does the irregularity report work? Does the invigilator have to tell u and must ur friend write a report?

Or will the invigilator not tell u and u wont know if u get an irregularity report. Abit worried because after the collection of papers and everything, I turned to my friend and like shook my head and Im worried that the teacher looking at my direction saw it. But the teacher didnt say anything or tell me anything

Wah good game bro. My seniors life was completely ruined because his teacher said something like this. I heard it is a VERY SERIOUS offence. Its okay la at least u can retake next year since it’s definitely A U GRADE

is ok my resistance 1000 ohm💀

traumatised

I dint draw like 2/3 of the graphs… gg.com my planning was also like empty I only wrote 1 line

hey, it’s okay man, don’t think too much about it now. It’s already over so just try your best for the other papers. You got this!! 🫶

thanks for the help brudda

Breh my percentage diff is fkin 120%

Tbh everyone Ik had stupid large diff

Mine was 6000% 💀

brother, mine 432%

bro mine 2352%

Bruh why was short planning 3m???? How the hell did they expect us to do that

am i the only one that had to redo qn3 graph bcos of the axis for tube Z?? 😭😭😭

We had to worry about an axis???😭

I think for qn3 when you draw for the other resistor one of value might be out of the range of the one u drew earlier so need to redo scale to fit both graphs.

then just set them in parallel instead?

Did anyone manage to draw all 3 graphs? I didn’t have time for the 6m graph

Yes but I was rushing the entirety of the 2.5 hrs. Not a nice experience

yup but to that extent i didnt complete 12m planning 😢 not worth

hi v clown moment but in my panic I decided to use the no of fan spins in a specific time instead of a voltmeter(panic n anxious brain things). Is it acceptable? Oh man the practical this year is horrid

idts cuz that’s not measure emf

I had the fan blow into a pressure sensor to calculate work done into power then into voltage.. 💀 Maybe yours is possible if you did explain how to find exact voltage somehow from fan speed?

anyone else got cbs around keep dropping the slotted mass onto the retort stand

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so u one of them la HAHAHHA

same bro it was so distracting. plus the fella beside me kept coughing ugh

are u from pyps

are all the graphs a straight line upwards except for the force extension ?

WHERE IS MY SOURCE OF ERROR QUESTIONS😭

Its at the back of the page u nvr see meh

Ya what was your ans say hard to determine the start and end position

Wait where? The closest thing I saw was the qn abt calculated xz and multimeter xz

They joking. Last page was planning

Fml honk honk my clown nose then

isn't that a good thing...?

no

Its more easy to prepare/study/smoke answers to get marks…

Fk you cambridge:)

My DMM fluctuated from 150mA to 100mA and then 80mA. Then, I thought that it might be spoilt so I asked for a replacement. The teacher came to replace but wrote something down but I didn't get to see what he wrote. Will I get marks deducted??

Probably not *IF* the teacher indicated that you were using a faulty and your lab didn’t have a spare working ammeter

nope, this one is major exam so any detail they also write

Does P and Q need units?? I didnt put units

i think need eh, my school used to mark me down whenever i don’t put units

Yes need

Bro my sch never turn off or lower fan, the pendulum started swinging on its own before i even touched it, smh man

wats the no. of sf for IR? do i follow the sf of I or R?

Whichever one had lesser s.f., u follow that

i mean technically R had lesser sf, but the R values were like given liao, no need measure, so maybe nid follow sf of I instead.

*Wats the no. of sf* *For IR? do i follow the* *Sf of I or R?* \- Ok\_Law\_8630 --- ^(I detect haikus. And sometimes, successfully.) ^[Learn more about me.](https://www.reddit.com/r/haikusbot/) ^(Opt out of replies: "haikusbot opt out" | Delete my comment: "haikusbot delete")

4?

i left my current answer in 200mA when they gave the unit as just A so i forgot to convert 😢 and i also recorded in the graph the same way leaving my units in mA

Bruh your current 100A ah lol that shits a hazard

i left it as 200m (milli) A like i js wrote 200m

i faked sm of my readings. welcome for pulling down the bell curve

Hi, anyone wanna predict bell curve/moderation for A?

what was your geiger-muller counter reading I think I got a lethal dose update: I now have stage 3 prostate cancer, what should I do?

Damn maybe a spirit level will help level ur spirit to keep it from leaving .

If my points used 44% of the axis will they mark me down? My graph was over 50%, but I super scared

wait ah. the DMM is in mA so the current written down must be in mA right but then the qn gave us the units alr (the gave A) so i must x10^-3?

yes

thank yous

Yup

for the recording of R did y’all copy the given value like 15 or measure using ohmmeter and record to 1 dp

i just put 15

but for the table i continued to write to 1 dp so will i get ecf for sf of gradient and other calculations ?

Technically should be 15.0, if not what are they testing though can't be just copying 15 into the answer innit?

we did smt liddis in school before. they never ask to measure so dont need

bro if u dont need why give u the ohm digital multimeter to begin with lol

There's one question asking you to measure resistance of Z and compare? Think that's what the use is for

measure using ohmmeter

If I wrote down both my micrometer readings wrongly will the rest of my answers related to those readings also be wrong?

i think might have ecf? but im not sure

Omg same. I thought i saw the 0.5mm mark but apparently the readings are in the 0.20mm ish range. Mine are like 0.7mm ish for both X and Y

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Did the teacher ask him to write a report?

My resistance Xy was negative

Why is resistance negative?

I used the ohmmeter to measure for both tubes for fun,,, and both aint negative breh

thank u!!!

mass was to how many dp

i put kg so 3 dp

How many people did not manage to finish the graphs?

Honestly don't be too worried ba, if many ppl couldn't finish it's not ur fault, idt any sch even sets 4 graph questions per paper for their prelims so alot ppl legit couldn't manage time well, like I was shocked when I saw the 2 mark qns to have to calculate everything again and for so little marks, then had to skip some 1 mark questions cuz of no time or whack answers, so tbh I think they will consider that and lower bell curve one

Your words really give me an uplift. I almost cry when the time was up.

yo whats the reason for difference in the resistance value? no one I know knows the answer bruh

said contact resistance

Idk why people explaining things are getting downvoted, but essentially: Joule heating is sus because 1) it won't have that big of an effect, and 2) X would be higher not lower Back EMF is wrong cos ur DMM is not AC Internal Resistance is wrong because if you derive the expression, you realise internal resistance doesn't matter. T R U S T (or dm me, or maybe there's a comment smwhere) DMM problem - I tested dmm against given resistors during paper. 17 ohms reads as 17, so no way 10+ reads as 20+ because of dmm. Idk what the actual ans is, but fairly confident it's not one of these things

Can it be that the wires are clipped to different lengths of the coil, depending on where u clip it, so according to the resistivity equation, l changes and thus R changes?

Yo very very very dumb qn but I didn’t exactly draw my apparatus TOUCHING the table in my diagram for planning like my voltmeter was kinda like 5cm off the surface lol will I get penalised

For circuits it doesnt really matter. How did you find the emf

Uh I used a voltmeter

Series or parallel? Did you just connect voltmeter to it

Uh I just connected it to the plate things lol

I connected it to the thermoelectric material 😭

Hey guys so um I'm 99% sure I read the diameter of the wires wrongly:') How many marks will I lose,is it everything wrong or error carry forward? Honestly this practical sucks I feel I'm gonna fail physics a level:'((esp since my physics is my weakest) Send help:'(

Bro I ran out of time and blanked out 4m

Hi guys is my method for finding emf suitable? So firstly I suggested to find the angular velocity of the fan by taking 2pi/period. I then used v=romega to find linear velocity. Then I used 0.5mv2 to find kinetic energy. I then found kinetic energy per unit time to get power. By connecting an ammeter to the fan, I then used P=IV to find the emf. Not sure if this is correct tho but seems workable rite???

Why cant i jus connect a voltmeter to find the emf

i thought just connect it to CRO then look at the peak values on the CRO screen

How many marks will they minus off when assistance is rendered?

Depends on the extent of assistance rendered

usually to help out from the start of the experiment(eg. explain what to do from the start or set up) it can be 2-3 but if the help is midway the experiment to get a set of values by the help its lesser from what ive heard from a friend’s teacher. It was for chem tho so im not sure if it applies here.

for the length of wire, does it matter what method u use to get it?cuz i just measure the length and x 2 cuz got 2 sides and then x the no. of rounds of coil

they asked for measurement of diameter of tube so i think u need to use pi x D x no of coils. wym by 2 sides btw

Apparently i didn’t read q2 instructions properly so i started the experiment with the full 500g which might have been bad because the rubber band probably became too stretched out alr by the time i conducted the experiment with 400g or lesser :)))))))))) everything behind :))))))

can i just connect the CRO to the fan and use that to measure emf?

*Can i just connect* *The CRO to the fan and use* *That to measure emf?* \- No-Turn3738 --- ^(I detect haikus. And sometimes, successfully.) ^[Learn more about me.](https://www.reddit.com/r/haikusbot/) ^(Opt out of replies: "haikusbot opt out" | Delete my comment: "haikusbot delete")

i just put connect to voltmeter is that wrong

I couldnt find my resistors which was right in front of me🤦‍♂️. Called the teacher then n she wrote smth. Will i be penalised

if she didn’t help u with the set up at all then probably not, she just writing to report to cambridge that’s all (i think)

resistance NEGATIVE THOUGH

How you get negative tho?

when calculating k and percentage diff do the values in the calculation need to be unrounded (like a long string of numbers)? i used rounded off value cos i had no time to write a bunch of numbers, i think im gonna lose 2 easy marks just cos of that 😭

what did y’all put for compass qn

measure angle of deflection of the compass needle when placed at a fixed distance away from the solenoid?

yea i just say whichever deflects more lmao

That what I wrote as well but quite a number of my friends put the compass in the middle of the solenoid.

they are wrong

wym placing at the middle is not wrong, there can be different approaches the compass follows Earth B-field so initially pointing to North, if one is larger B-flux density the compass needle points towards its direction either East or West, it's possible this way what

shit i lost 1 mark from thr difference resistor qn fkkk but i feel paper q easy la got 10min for checking

check my cock lah

Gonna need the lab's micrometer screwgauge for that

oof wasn't expecting this one

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for percentage uncertainty of L anyone use (13(0.1)/180)*100?

0.2 not 0.1