Physics P1 and P2: Discussi0n

[Mobeen]

yea .. after every ppr there is one stupid question over which everyone fights.. there was one in chem too..!

 

[allthatglitters16]

LIMIT WAS ASKED.
100% SURE
ANSWER WAS P WHICH WAS OPTION C
20000000% CONFIRM

 

[Mobeen]

yep !! CONFIRMED FOR SURE !!

 

[BILALrox01]

Firstly people let me clear your confusion about the Q of principal conversion of energy. KINETIC ENERGY=1/2 mv2..... sahi baat? there is no acceleration involved in gain of kinetic energy and so only velocity needed... Wether the velocity was constant or not there will be an increase in the kinetic energy according to the equation.. and he was falling so potential energy was being changed to kinetic energy... they had asked about the PRINCIPLE conversion, though heat is also produced but principally it was PE to KE... hope this clears.
And secondly the sec B last Q had a curve, current not necessarily becomes constant but there is a turn.. see the buk... u ll find a curve for a filament lamp.

P.E=mgh....rite. suppoz m=60 g=10 and h=10000
P.E will then be =6000000j....rite
K.E= 0.5 m vsquare rite.... nd v increases to 150m/s
K.E=675000
From 6 MJ only 0.675 MJ converted to K.E...Wherz the rest gone. R u saying K.E is calculated by the second
then P.E should be calculated by the second too.
@ 15 sec nd 1200 m he reached this speed ok
so rest of the distance is there no change to any other form of energy
plus its written somewhere in xplaining physics.

 

[BILALrox01]

By the second it becomes every second .6 MJ of K.E but the P.E every second decreases...is it going up your...

 

[Zishi]

yep !! CONFIRMED FOR SURE !!

LOL. It is a repeated question, search for it in previous papers of 2007, 2008 and 2009. See its marking scheme. Whatever was asked, the answer was OP.

 

[BILALrox01]

what momen said is not true

tell me that if the P.E is being converted to K.E at a constant rate, even then the K.E is not increasing but remaining the same.That means that the K.E is also being converted to Heat. They asked for PRINCIPLE CHANGE which would then be P.E to Heat

P.E to Heat is 100 %
wrong .!


i have confirmed it from akhter mehmood my acdmy sir.!!

Time to change academy dude

 

[BILALrox01]

The MCQs R checked by a computer so ther is no range of answers
P.E to heat hai waha jaha heat se jalne ki baat hai to comets jab atmosphere mai atei hai kya friction se rakh nae ho jatei...??

 

[Hashim]

what momen said is not true

tell me that if the P.E is being converted to K.E at a constant rate, even then the K.E is not increasing but remaining the same.That means that the K.E is also being converted to Heat. They asked for PRINCIPLE CHANGE which would then be P.E to Heat

P.E to Heat is 100 %
wrong .!


i have confirmed it from akhter mehmood my acdmy sir.!!

Time to change academy dude

her brother, you will not find a teacher better than sir.Akhtar mahmood...!!

 

[Mobeen]

yea man !! there is no beter teacher thn him .. aiwein to nae top ka teacher kaha jata ..
nd zishi .. yea its a repeat question nd the answer is P ...

 

[book worm]

yep !! CONFIRMED FOR SURE !!

LOL. It is a repeated question, search for it in previous papers of 2007, 2008 and 2009. See its marking scheme. Whatever was asked, the answer was OP.

I donot want to make this post because its just silly that we are fighting over some stupid mcqs

however, zishi, the question asked that which part of the graph showed the limit of proportionality which was P. if it had asked that in which region/part of the graph Hooke's Law was obeyed then it was to be OP.

OK now we shouldnot fight over the content of the questions and lets close this chapter in peace!!

 

[Mobeen]

yea.. its confirmed tht the answer was P .. quit fighting over it ...

 

[sunshine]

thank GOD .!
it is gravitational energy into kinetic .!

look guys i know the mass and Velocity of parachute was constant but this does not mean that gravitational potential energy is not converting into kinetic energy ,,this means that there is a constant rate at which gravitational potential energy is changing into kinetic energy .!!

secondly there was also change of gravitational potential energy into heat but it was negligible as compared to kinetic energy .!
my sir explained me bout that

 

[Mobeen]

.. here we go again..
nd whos ur sir .. where do u study ..

 

[OakMoon!]

yep !! CONFIRMED FOR SURE !!

LOL. It is a repeated question, search for it in previous papers of 2007, 2008 and 2009. See its marking scheme. Whatever was asked, the answer was OP.

ON 2006 Q7.. answer was P my bro... i did OP wehn praciticing but its wrong and so didnt forget this during the paper

 

[OakMoon!]

Firstly people let me clear your confusion about the Q of principal conversion of energy. KINETIC ENERGY=1/2 mv2..... sahi baat? there is no acceleration involved in gain of kinetic energy and so only velocity needed... Wether the velocity was constant or not there will be an increase in the kinetic energy according to the equation.. and he was falling so potential energy was being changed to kinetic energy... they had asked about the PRINCIPLE conversion, though heat is also produced but principally it was PE to KE... hope this clears.
And secondly the sec B last Q had a curve, current not necessarily becomes constant but there is a turn.. see the buk... u ll find a curve for a filament lamp.

P.E=mgh....rite. suppoz m=60 g=10 and h=10000
P.E will then be =6000000j....rite
K.E= 0.5 m vsquare rite.... nd v increases to 150m/s
K.E=675000
From 6 MJ only 0.675 MJ converted to K.E...Wherz the rest gone. R u saying K.E is calculated by the second
then P.E should be calculated by the second too.
@ 15 sec nd 1200 m he reached this speed ok
so rest of the distance is there no change to any other form of energy
plus its written somewhere in xplaining physics.

K.. i knw i am rong... i searched google....TERMINAL VELOCITY IS NOT IN OUR SYLLABUS still a Q came on it

 

[Zishi]

Oh. I remember that. My answer's wrong, then.

 

[Mobeen]

same here hamidali.. i also did it wrong during practice .. remembrd it in the final ppr ..

 

[Zishi]

same here hamidali.. i also did it wrong during practice .. remembrd it in the final ppr ..

I did it correct while practicing, but now I did it wrong in the paper. Dammit!

 

[M.Usman Khan]

thank GOD .!
it is gravitational energy into kinetic .!

look guys i know the mass and Velocity of parachute was constant but this does not mean that gravitational potential energy is not converting into kinetic energy ,,this means that there is a constant rate at which gravitational potential energy is changing into kinetic energy .!!

secondly there was also change of gravitational potential energy into heat but it was negligible as compared to kinetic energy .!
my sir explained me bout that

ok lets look at the qs logically.....
first v all agree the Speed was constant....
now v all also agree the man was falling down.....
the man was falling down....meaning the potential energy was decreasing... :mrgreen: :mrgreen: :mrgreen:

Now the qs arises where does this energy go???????????? :?: :?: :?: :?:

lets think :idea:
could it b kinetic energy :| :?:

:arrow: the ans a big NOOOOOOOOOO :!: :!: :!:

reason: if potenial energy was changing into kinetic then kinetic energy should b increasing bcoz potential energy is decreasing(common sense)

well if not kinetic than what :?: :?: :?: :geek: :ugeek: :idea:

it should b heat energy....it was the only other option. DUH!!!!! :!: :!: :! :twisted: