Biology; Chemistry; Physics: Post your doubts here!

[asma tareen]

doesnt everyone do that???

 

[nidz]

simple. bring a lighted splint near the source, the splint extinguishes with a pop sound. y risk any of your precious marks?

Yeah but from what I remember they also say that it is the hydrogen that pops not the splint :/ Or something like that So the word have to be really really clear :S

 

[tdk]

Re: Biology,Chemistry & Physics Help Available Here !

thanks for the positive response ! i appreciate it !

anyways anyone has any questions we will be happy to solve them !

Could u plz give me the past Question Papers and Mark Schemes of PHYSICS, CHEMISTRY, BIOLOGY AND Maths B and Add Maths from 1990 till 2002 which I could not find. Plz help me.

 

[tdk]

Re: Biology,Chemistry & Physics Help Available Here !

sorry about mixing it up.... i was in a hurry.... and yes. i did get but i was a little stuck on a 87 past paper question.... so no biggie. =) thanx btw.

Could u plz give me the past Question Papers and Mark Schemes of PHYSICS, CHEMISTRY, BIOLOGY AND Maths B and Add Maths from 1990 till 2002 which I could not find. Plz help me.

 

[asma tareen]

www.freeexampapers.com
check it out here???

 

[nidz]

We never wash out flasks with acids/alkalis. We only rinse burettes with the solution to remove the water, we rinse it several times, and we reduce the error as far as we can! Excess solution of the acid in the burette is not an impurity, water is.

I think the question in Nov 11 that everyone is debating about is a little different from that of June 2002. It's asking about the flask that contains alkali...Whose concentration doesnt really matter since we only note the volume of the acid in the burette. That is why only water should be used. But for the burette u wash it with water and acid to make sure it has the same concentration
Does this make sense?

 

[Suchal Riaz]

doesnt everyone do that???

no most people memorise: E=ml, e=mc thta
but mostly i do MOST of my calculation by looking at left and right hand side of my equation by units. i make equation in mind. i learned it from first year physics course from MIT it's a kind of quick dimensional analysis to check ur method.

 

[tdk]

www.freeexampapers.com
check it out here???

THANKS. I'm CHECKING NOW

 

[asma tareen]

no most people memorise: E=ml, e=mc thta
but mostly i do MOST of my calculation by looking at left and right hand side of my equation by units. i make equation in mind. i learned it from first year physics course from MIT it's a kind of quick dimensional analysis to check ur method.

well i used the same technique and our teacher wx amazed cux i did the questions of some of the topic he hadnt taught us yet and i wx able to figure out the formula

 

[asma tareen]

sorry it starts from 2000

 

[Suchal Riaz]

a quick question:
Q8bi part and last question of the paper. can u please explain me.
asma tareen

 

[asma tareen]

i can try m not that good

a quick question:
Q8bi part and last question of the paper. can u please explain me.
asma tareen

 

[Saad Mughal]

so u also do these calculations by looking at units
i though that it was just me does not memorise "mltheta weeta blah blah" but look at units to get answer

Well yeah, if you know the units, you know the conversions and the equations! Simple as that, no need to memorize anything, no need to get confused.

 

[Saad Mughal]

I think the question in Nov 11 that everyone is debating about is a little different from that of June 2002. It's asking about the flask that contains alkali...Whose concentration doesnt really matter since we only note the volume of the acid in the burette. That is why only water should be used. But for the burette u wash it with water and acid to make sure it has the same concentration
Does this make sense?

Yes, that's why we wash flasks only with water!

 

[Saad Mughal]

a quick question:
Q8bi part and last question of the paper. can u please explain me.
asma tareen

Which (b)?
There are two (b)'s.

 

[asma tareen]

hmm i think the total moment would be o.8 Nm cux at both sides the length and force is same and the direction of the rotation is also same m not sure
m= f*d
20*o.o4
80Nm

 

[Saad Mughal]

hmm i think the total moment would be o.8 Nm cux at both sides the length and force is same and the direction of the rotation is also same m not sure

You're right, the coil is rotating clock-wise (one direction) hence the total moment = moment at AB or moment at CD = 20*4 = 80 N cm = 0.8 N m.

 

[asma tareen]

You're right, the coil is rotating clock-wise (one direction) hence the total moment = moment at AB or moment at CD = 20*4 = 80 N cm = 0.8 N m.

yayyyyy m right

 

[Saad Mughal]

yayyyyy m right

 

[asma tareen]

yar jis ny pucha tha wo kidr gaya