Physics: Post your doubts here!

[A*****]

Congratulations!!

Thanks! How was yours?

 

[Hamnah Zahoor]

Thanks! How was yours?

Alhamdulillah ...3As
I am studying only 3 subjects in A level.

 

[Kanekii]

Should i give my papers for rechecking?
Getting Cs is really a big surprise for me since i was expecting As and even my papers went good and i discussed the papers thoroughly with others and even checked on this forum and my answers matched.
I worked superhard from start since i knew from start A levels is tough. I read the coursebooks number of times, read notes and other resource books, revised them, did topical past pastpapers whole book and then did yearly pastpapers of 10 years. Even made my own notes and revised them. I basically did everything and still it was inevitable to get the grades that i wanted. I feel shattered..

 

[anastasia grey113]

Should i give my papers for rechecking?
Getting Cs is really a big surprise for me since i was expecting As and even my papers went good and i discussed the papers thoroughly with others and even checked on this forum and my answers matched.
I worked superhard from start since i knew from start A levels is tough. I read the coursebooks number of times, read notes and other resource books, revised them, did topical past pastpapers whole book and then did yearly pastpapers of 10 years. Even made my own notes and revised them. I basically did everything and still it was inevitable to get the grades that i wanted. I feel shattered..

um dude
if u think u can do it then u may take a retake but lemme tell u something
the overall A2 gt will be different for u if u retake AS in Oct Nov...its usually higher
this session I had a few frnds of mine who had taken AS in oct nov and guess wut? they declined from A in AS to B overall
so if u r planning to retake it, be prepared for struggling very very hard in A2.

or if u dont want to retake anything, you can convert ur Cs to As in A2 too.

theres a third alternative tho
take composite subjects...forget this result and start over
revise concepts of AS Levels whilst studying for A2.
Then take all the papers together and you might get an A* then.
I'm not sure but I think that the situation will be not be the same next year.
The gt should be lower.
You'll have to push urself more tho and you will need to double all the efforts.

Now its up to u
Do what you think would be best for you.

 

[DentedBend]

Should i give my papers for rechecking?
Getting Cs is really a big surprise for me since i was expecting As and even my papers went good and i discussed the papers thoroughly with others and even checked on this forum and my answers matched.
I worked superhard from start since i knew from start A levels is tough. I read the coursebooks number of times, read notes and other resource books, revised them, did topical past pastpapers whole book and then did yearly pastpapers of 10 years. Even made my own notes and revised them. I basically did everything and still it was inevitable to get the grades that i wanted. I feel shattered..

Which subjects did you write? For subjective subjects like English etc, maybe rechecking is worth it but for maths or physics etc, it's generally not worth it. When you get your PUMS, you can do some calculations using the current and past grading thresholds to approximate the marks that you need in A2.

Generally, people who retake in my school opt for AS and A2 together because A2 syllabus does assume AS knowledge.

 

[Kanekii]

Which subjects did you write? For subjective subjects like English etc, maybe rechecking is worth it but for maths or physics etc, it's generally not worth it. When you get your PUMS, you can do some calculations using the current and past grading thresholds to approximate the marks that you need in A2.

Generally, people who retake in my school opt for AS and A2 together because A2 syllabus does assume AS knowledge.

So if i were to retake my exams should i give them in May with my A2s or Oct/nov?

 

[Hamnah Zahoor]

So if i were to retake my exams should i give them in May with my A2s or Oct/nov?

I would advise you to give them in may as composite because you know A2 is also difficult and if you keep on preparing for A1 till oct than you will have very little time left for A2 which will be a disadvantage.
A2 syllabus includes all that learned in A1 and A2 thus it will also help you revise for your paper 4 & 5.
Stay calm ...stay focused and work hard for the next 6 months and please try and stay away from every leisure activity.
This is a very precious time don't waste it.
Inshallah you will be successful.Work hard and leave the rest to Allah.

 

[Psyvlone007]

yar i need an advice
I studies very hard and I gave papers and i knew i would be getting As in them I crosschecked all the ans and they were around 30s but the results contradict the,m , they went really really greatttt ik
but my result turned out to be very poor
now what should i do
Retake
Recheck
Composite
and as I have Bio and i really want to get in a Govt medical college is it practical that I switch to fsc and work hard ??

 

[anastasia grey113]

yar i need an advice
I studies very hard and I gave papers and i knew i would be getting As in them I crosschecked all the ans and they were around 30s but the results contradict the,m , they went really really greatttt ik
but my result turned out to be very poor
now what should i do
Retake
Recheck
Composite
and as I have Bio and i really want to get in a Govt medical college is it practical that I switch to fsc and work hard ??

id rather u stick to A Levels for now.
Becuz its in equivalence of A Levels where v have a margin. We get marks as high as 990 and 970 which FSc students cant even dream of getting
sure it will be a challenge doing the mcat but ask urself....would u want to revise wut youve already studied and go for a retake or would you waste wutever u learned in ur last year and will start over with FSc which has unjust marking and wont score you as much as A Levels can?

 

[Psyvlone007]

id rather u stick to A Levels for now.
Becuz its in equivalence of A Levels where v have a margin. We get marks as high as 990 and 970 which FSc students cant even dream of getting
sure it will be a challenge doing the mcat but ask urself....would u want to revise wut youve already studied and go for a retake or would you waste wutever u learned in ur last year and will start over with FSc which has unjust marking and wont score you as much as A Levels can?

but see there are also students that get around 1020 1030 in Fsc with studying i guess even less than what we have to study for A*s

 

[A*****]

Which subjects did you write? For subjective subjects like English etc, maybe rechecking is worth it but for maths or physics etc, it's generally not worth it. When you get your PUMS, you can do some calculations using the current and past grading thresholds to approximate the marks that you need in A2.

Generally, people who retake in my school opt for AS and A2 together because A2 syllabus does assume AS knowledge.

What is PUMS?

 

[DentedBend]

What is PUMS?

http://www.cambridgeinternational.org/images/209304-a-guide-to-percentage-uniform-marks.pdf

 

[anastasia grey113]

but see there are also students that get around 1020 1030 in Fsc with studying i guess even less than what we have to study for A*s

Well in my school, people literally study wayyyyy more. I'm talking about the FSc candidates.
Here are a few cons:
1- An increased number of subs. You'll have to appear for 8 subs instead of 3.
2- No sense of concepts. People do say it's all concept but in the end, the one who crams the best comes out as the high scorer and Cambridge students are never made to go on that track. So it will be difficult for you to adapt.
3- Islamiyat and Urdu in Urdu. You'll have to learn all the tashreehs and summarys in Urdu and Islamiyat?? Well that's in Urdu too. So basically, you are stuck with the same subs u thought u had gotten over with in O2.
4- Unjust marking. You know the yearly protests students do due to unfair marking by the examiners. I've literally heard stories of toppers failing in FSc and they have no explanation for that. All they say is 'Hard luck ho gai.' <----you see this does not happen in cambridge at all.
5- They study a lot. We just have 9 papers to focus on in AS. They have around 20.
6- In p3 you are given the instructions but in FSc practicals, you have to 'learn' the practicals. By that I mean performing the experiment beforehand, taking the readings and learning them becuz sometimes apparatus is not available. And also the countless salt analysis tests. Yes you have to learn them.
7- There's viva too. Pure luck.
8- Oh the struggle with the practical notebook which holds just two marks.

And even after all that, people fail to get 92%.

I would still recommend taking A Levels becuz they reward you marks based on ur performance in the paper. Not on the status of your dad or the amount of money he has offered.
And yh, students who are top scorers are usually the ones who are used to cramming since theyve been doing this since the 9th grade. But you haven't. So you have to consider that too. Things which are hard for matric students will be harder for you.

 

[A*****]

http://www.cambridgeinternational.org/images/209304-a-guide-to-percentage-uniform-marks.pdf

Surprising...this doesn't appear on our statements

 

[anastasia grey113]

Surprising...this doesn't appear on our statements

well u must be a pakistani candidate then
it used to show up until in 2010, there was some issue with equivalence n all...long story
so they stopped sending PUMS here.

 

[A*****]

well u must be a pakistani candidate then
it used to show up until in 2010, there was some issue with equivalence n all...long story
so they stopped sending PUMS here.

That's bad

 

[anastasia grey113]

That's bad

yh
it was like...a student who got a 65/100 in Islamiat was given an A* according to threshold but the PUMS was written as 60% so the IBCC was accepting the PUMS instead of the grade (in this case, the 60% was considered for equivalence, not the 90% for A* as its done now) This put the CIE students at a disadvantage.
So the IBCC stopped CIE to send PUMS from then on and alotted marks to each grad by themselves e.g 90 for A*, 85 for A and so on.

 

[A*****]

yh
it was like...a student who got a 65/100 in Islamiat was given an A* according to threshold but the PUMS was written as 60% so the IBCC was accepting the PUMS instead of the grade (in this case, the 60% was considered for equivalence, not the 90% for A* as its done now) This put the CIE students at a disadvantage.
So the IBCC stopped CIE to send PUMS from then on and alotted marks to each grad by themselves e.g 90 for A*, 85 for A and so on.

Ohh right!

 

[Mijandi@7]

Need some help over here

A small diesel engine uses a volume of 1.5 × 104 cm3
of fuel per hour to produce a useful power
output of 40kW. It may be assumed that 34 kJ of energy is transferred to the engine when it uses
1.0 cm3
of fuel.
What is the rate of transfer from the engine of energy that is wasted?
A 102 kW B 142 kW C 182 kW D 470 kW

Don't understand how to get the Answer which is A. Help is appreciated thanks

 

[anastasia grey113]

Need some help over here

A small diesel engine uses a volume of 1.5 × 104 cm3
of fuel per hour to produce a useful power
output of 40kW. It may be assumed that 34 kJ of energy is transferred to the engine when it uses
1.0 cm3
of fuel.
What is the rate of transfer from the engine of energy that is wasted?
A 102 kW B 142 kW C 182 kW D 470 kW

Don't understand how to get the Answer which is A. Help is appreciated thanks

Since we are talking in terms of power which is energy per second, we should be doing all our calculations of energy for 1 second only.

Well the volume is 1.5 x 10^4 per hour so per second the volume consumed should be
1.5 x 10^4/3600 = 4.17 cm3 <------ this is the volume consumed per second.

Now the energy transferred per second will be
4.17 x 34 = 141.7 kJ <----- it can be called the power transferred to the engine as well becuz its energy per second right?

Moving on to the power wasted.
Now the 141.7kJ is the TOTAL power.
While 40kJ is the useful power.
So to find the waste --------> total - useful = 141.7 - 40 = 101.7
Round it off to 102 kJ
Hoping it helped