Physics, Chemistry and Biology: Post your doubts here!

[Tekno-M]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s08_qp_6.pdf
Question 1)b

 

[ZainH]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s08_qp_6.pdf
Question 1)b

Not my answer, found this in another thread where a person asked the same question.

"Mark the centre of the cylinder, measure the cylinder.
After the measurement, place it on the metre rule. It should cover up the area we measure (for eg. 2cm)
So it'll cover the area between 8 - 1o and or 9 - 11 and so on..
If length of the cylinder is 2 cm, make sure to place it at 9 cm and so it ends at 11 cm, being 10 in the middle."

Credits for answer go to wooowooowoo

 

[shafayat]

plz can sm1 give the defination of the mole and avogardos constant ?

 

[ZainH]

plz can sm1 give the defination of the mole and avogardos constant ?

A mole if 6.02x10^23 particles of any substance.
It's basically a unit of measurement if you think about it, like a dozen is = 12, a mole is = 6.02x10^23
Hope this helped x)

 

[shafayat]

A mole if 6.02x10^23 particles of any substance.
It's basically a unit of measurement if you think about it, like a dozen is = 12, a mole is = 6.02x10^23
Hope this helped x)

I acctually wanted an official defination ..
=] plz

 

[kainat husain]

kainat husain Look,
the question states that u need to draw a circuit which is similiar to (ii) using a lead (connecting wire) and u need to use standard symbols to show AB BC & CD but there is 1 more condition they want u to connect resistors A & D together
so using the symbol of resistor we draw AB & BC now the problem is CD in the diagram(ii) CD is connected to C but not to A so in ur diagram u need to connect it to A wen u do it, this is wat u'll get

thankkkkkkkkkkkkkkkkkkkkkkkk uuuu soooooooooooooo much silly me:/ thank uu

 

[Huzza]

how can we judge that the centre of an object is directly above a specific mark on a rule?

 

[wooowooowoo]

Not my answer, found this in another thread where a person asked the same question.

"Mark the centre of the cylinder, measure the cylinder.
After the measurement, place it on the metre rule. It should cover up the area we measure (for eg. 2cm)
So it'll cover the area between 8 - 1o and or 9 - 11 and so on..
If length of the cylinder is 2 cm, make sure to place it at 9 cm and so it ends at 11 cm, being 10 in the middle."

Credits for answer go to wooowooowoo

Naww, don't give me credit. I posted the answer so you can understand and manipulate it on your own.

 

[thats_me]

thankkkkkkkkkkkkkkkkkkkkkkkk uuuu soooooooooooooo much silly me:/ thank uu

lol no problem n ur most welcum

 

[kainat husain]

I acctually wanted an official defination ..
=] plz

A mole (molar mass) of any susbtance is it's relative atomic number (AR) or relative molecular mass (Mr) (if it is a compound) measured in grams

 

[AAnsarii]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s10_qp_61.pdf
sby plz 4(b)!!!

 

[ZainH]

I acctually wanted an official defination ..
=] plz

That is the official definition..
"A mole is 6.02x10^23 particles of a substance"

Naww, don't give me credit. I posted the answer so you can understand and manipulate it on your own.

Credits gotta be given where it's due, and besides..if I didn't give credit, people would think it was my answer x)

 

[knightwalker]

what is the limit of experimental accuracy and how do you know if your measurment lies within the limit of experimental accuracy?
also how do you make sure that the center of an object lies within a certain mark on a ruler?
PLEASE i need help asap it has come up a couple of times in the pp's
Thank youu!

 

[ZainH]

I acctually wanted an official defination ..
=] plz

Definition from my book: The relative formula mass of a substance in grams.

Definition from mark scheme:
-Avogadro’s Number of particles
-Formula mass in grams
-6 x 10^23 particles accept atoms, ions and molecules
-As many particles as there are carbon atoms in 12.00g of 12Ca

As you can see the definition I gave is one of the correct definitions in the mark scheme x)

 

[AAnsarii]

what is the limit of experimental accuracy and how do you know if your measurment lies within the limit of experimental accuracy?
also how do you make sure that the center of an object lies within a certain mark on a ruler?
PLEASE i need help asap it has come up a couple of times in the pp's
Thank youu!

xperimental acc. i dunno
centre--if d object is 4cm, n its supposed 2 b on 10.0cm mk, 2 cm should b on either side, so 1st side= 10-2= 8cm, n d other side 10+2 = 12cm
sorry 4 d xperi.acc.
all d best.

 

[ZainH]

what is the limit of experimental accuracy and how do you know if your measurment lies within the limit of experimental accuracy?
also how do you make sure that the center of an object lies within a certain mark on a ruler?
PLEASE i need help asap it has come up a couple of times in the pp's
Thank youu!

Within limits of experimental accuracy means your answer should be within a range of reasonable answers..
It shouldn't be some random number that you just thought of and wrote down, it should be a sort of estimate of the actual answer.

 

[NIM]

Guys!!!
Room temp is 23 or 24 degree C...
Confused a bit

 

[ZainH]

Guys!!!
Room temp is 23 or 24 degree C...
Confused a bit:d

23 degrees usually.

 

[EpicLol]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s08_qp_6.pdf
Question 1)b

Get the center of the cylinder, then extend the line onto the ruler, then remove the cylinder and read the mark....

 

[thats_me]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Physics (0625)/0625_s10_qp_61.pdf
sby plz 4(b)!!!

here hope u get it