Physics exam 31 came from heeeeeel!!!!! What is wrong CIE

[Divalicious]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

@unplugged: yep
I designed an experiment to find out the critical angle of light in glass since:
(1/sin critical angle) = (Speed of light in air/Speed of light in glass)
Then we can calculate the light speed in glass. The idea seems right but the procedure I explained to find the critical angle is ...idk not sure xD

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

oh erm. well i mean 1/sin critical angle is valid sure. But sin i/ sin r is speed of light in air / speed of light in glass . For any ray regardless of it being completely internally reflected.
you'll probably get most of the marks i reckon , if not all.

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Do you remember the value for the resistance in that circuit with the variable resistor , trying to give the lamp optimal P.D.

 

[Divalicious]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Urgh....can't remember that lol

 

[Ahmooosh]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Do you remember the value for the resistance in that circuit with the variable resistor , trying to give the lamp optimal P.D.

I cant remember , which value did u use though? one in the circuit pic or the one given in the text , also for the circuit diagram , it said using mains supply, how did u draw it? just the power thingy.

 

[Divalicious]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Do you remember the value for the resistance in that circuit with the variable resistor , trying to give the lamp optimal P.D.

I cant remember , which value did u use though? one in the circuit pic or the one given in the text , also for the circuit diagram , it said using mains supply, how did u draw it? just the power thingy.

You should use the one in the text.
And for the the mains supply, I guess it's just like 'power supply'; the two lollipops[thats what I call the two lines with a circle at the end of each] with 'power supply' written in between xD

 

[Ahmooosh]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

okie cool , i also used on in text , for power i used a circle and like ac wave in it , wrote ac supply
;p

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Do you remember the value for the resistance in that circuit with the variable resistor , trying to give the lamp optimal P.D.

I cant remember , which value did u use though? one in the circuit pic or the one given in the text , also for the circuit diagram , it said using mains supply, how did u draw it? just the power thingy.

I think i got the resistance as something along the lines of 1.9 ohm.

 

[Ahmooosh]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

i think same here , first page , last question , how many ,,,,, can he do in 5 sec . damn that was hard, spent ages then noticed that time was running out so just wrote 9, dunno how i got it though... whats ur thought on that?

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

If you're referring to the ladder question. It works out to 11 i'm afraid. calculated work to climb one , then divided that by power to get how many he got in a second and then multiplied that by 5. Worked out to 11 exactly.

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Honestly the exam would have been a lot nicer if it lasted like 15 minutes longer. I mean , these aren't generic questions that we're supposed to instantly figure out. They require a bit of logic.
The way the exam went was that you had to write down your first impression , else you lost marks by missing easy questions that are later on because time would run out.

 

[Divalicious]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

@unplugged
yep it's 11 ladder rungs ^^

 

[narutogirl]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

well i entered the exam knowing i will repeat it in november..i sit the 15 min b4 the exam praying and then she gives us the papers..i look...wth..20 papers..ok
i open then i say ok extension not bad..then i look at the rest..i dunno this, this nor this, wtf is this..oh my gosh i keep fliping
then i become like O.O"
so ya -____-.....exam from hell is such a good discribtion..lol i was like sh*t sh*T through the whole test and i forgot half the equations..like urghh

 

[Ahmooosh]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

yea exactly , i spent like lots of time on the ladder question and the one that follows , didnt get an answer so just skipped , same thing with fibre optics question , the last 3 parts.... i was running out of time , when i finish the paper we had 5 mins left , so i just filled in the spaces with mostly non sense.... wth was that question , use ur gradient from c to calculate the mass , F=MA , M=F/A , what is the gradient supposed to be ? A or F , and what about the other value? i hated this question.

also for the bubbles volume question , we were supposed to use p1xv1 = p2xv2?

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

How did you calclulate the volume of the bubble and what did you say about the temperature increase.
I just assumed that pressure at bottom x volume at bottom = pressure at top x volume at top and got the volume that way. And said that the volume would have increased if the temperature increased. Seems sensible since things expand under heat >_>.

 

[Divalicious]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

@Ahmooosh
Yep, you'll get 1.1 cm3 for the bubble volume but what about the following question?
I wrote that the calculated volume is less than the actual.

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

yea exactly , i spent like lots of time on the ladder question and the one that follows , didnt get an answer so just skipped , same thing with fibre optics question , the last 3 parts.... i was running out of time , when i finish the paper we had 5 mins left , so i just filled in the spaces with mostly non sense.... wth was that question , use ur gradient from c to calculate the mass , F=MA , M=F/A , what is the gradient supposed to be ? A or F , and what about the other value? i hated this question.

also for the bubbles volume question , we were supposed to use p1xv1 = p2xv2?

I'm not sure about the gradient one. But it seemed to me that the gradient was indeed F/A which is the Mass if you think about it. So i assumed it wrote down the equation for mass and then assumed the gradient was the mass. I think there was probably more to it , being a two mark question and all.

 

[Ahmooosh]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

i wrote then my answer for the previous question would not be correct , since temperature must remain constant in order for boyles law to work. that was my desperate answer after wasting much time and thought about them.
what did u use for pressure at top? just the atmospheric pressure?

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

Yea , at the top it would just be atmospheric pressure

 

[unplugged]

Re: Physics exam 31 came from heeeeeel!!!!! What is wrong CI

How did you handle the gradient question then?