Physics: Post your doubts here!

[allysaleemally]

Hello,

which calculators can be used in AS Maths and Physics.
is this Casio one allowed http://edu.casio.com/products/standard/fx991es/
or do we have to use the basic one: http://edu.casio.com/products/standard/fx85ms/

some people say that u cant use the Fx 991 calculator(silver one)?

 

[Ashique]

You are only interested in the current going through the 6 ohm resistor not the total current leaving the battery. The answer does not depend on the resistance of the variable resistor only the amount of the variable resistor that is in parallel with the 6 ohm resistor.

If the arrow was in the middle of the variable resistor then the 6 ohm resistor would be in parallel with 1/2 of the variable resistor. There is a 12 volt drop across the variable resistor and one half or 6 volts would also be across the 6 ohm resistor and there would be 1 amp through the 6 ohm resis

Right, so we are interested in the current across the 6 ohm resistor due the positioning of the ammeter. Thanks!

 

[Ashique]

Hello,

which calculators can be used in AS Maths and Physics.
is this Casio one allowed http://edu.casio.com/products/standard/fx991es/
or do we have to use the basic one: http://edu.casio.com/products/standard/fx85ms/

some people say that u cant use the Fx 991 calculator(silver one)?

You can use both. The first calculator (fx991es) is easier to work with, imo. Makes fractional and calculations involving indices much easier, I highly recommend it.

 

[Ashique]

worksheet 12, Q. 6 c part] (why is the ms saying dat current in lamp increases proportionally with resistance?)
R= V/I so current decreases with increase in resistance...:/

Yep, the ms is wrong. The graph also shows a positive gradient of the I-V graph., so it's somewhat proportional, if not direct.

 

[Ashique]

Also, where are you people getting these worksheets? They seem quite helpful for revision. Can someone please post the link?

 

[usmiunique]

ASA,
i have many questions regarding paper 5. can anyoneplease tell me:
1) what is meant by error bars?
2) what is meant by worst acceptible line?
3) how do u calculate the error in the gradient?
4) how do u calculate the error the tabulated values which u have to calculate?
Also any notes on the apparatus and their use and how to write different kinds of experiments would be greatly appreciated!

 

[hassam]

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_w10_qp_43.pdf

please explain question number 3

can u be more specific please cos its a very long question.....i guess u ll be asking for that not in phase thing cos dats the difficult part in this.....so wat u need to do is to do a graph for original equation given prev. in question......and then shift it horizontal by 120 deg. in right direction.....one can ask why not in left direction ...thats because oscillation in that cylinder lead those of in prev by 120 deg....similarly do for 240 deg. phase shift....and then u cn see the displacemnt .....and thus draw positin of piston

 

[hassam]

ASA,
i have many questions regarding paper 5. can anyoneplease tell me:
1) what is meant by error bars?
2) what is meant by worst acceptible line?
3) how do u calculate the error in the gradient?
4) how do u calculate the error the tabulated values which u have to calculate?
Also any notes on the apparatus and their use and how to write different kinds of experiments would be greatly appreciated!

 

[rz123]

Yep, the ms is wrong. The graph also shows a positive gradient of the I-V graph., so it's somewhat proportional, if not direct.

thanks. a guy uploaded dez worksheets here nd they also come along with the Cambridge endorsed book in a cd..
already uploaded worksheet 1 so rest r below with marking schemes..

 

[usmiunique]

Thnx a MILLION... May ALLAH bless u with success both in this world and in the hereafter!
I owe u one!

 

[hassam]

Use the first law of thermodynamics to explain why the specific latent heat of
vaporisation is greater than the specific latent heat of fusion for a particular
substance.

 

[XPFMember]

Use the first law of thermodynamics to explain why the specific latent heat of
vaporisation is greater than the specific latent heat of fusion for a particular
substance.

Assalamoalaikum wr wb...

Here's what my book says: Volume changes associated with evaporation are much greater than those associated with melting. The external work done is much greaater during vaporisation, and thus latent heat of vaporisation is much greater than latent heat of fusion.

 

[XPFMember]

aoa!
I got a doubt in nov 2011 paper 4 Q:3 b ii
ms says thermal energy is derived from energy of oscillation of the magnet

i dont understand :s

 

[Tatenda]

thanks. a guy uploaded dez worksheets here nd they also come along with the Cambridge endorsed book in a cd..
already uploaded worksheet 1 so rest r below with marking schemes..

Can you post the answers to chapters 17 upwards please

 

[Ashique]

Can someone help me with Q 3 c ii?
http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_s07_qp_2.pdf

 

[Duanoor]

hey...i did o levels and thn opted for fsc...i am struggling with a question...can u guys hlp me??
we read that in solids speed of sound is greater cz its density is greater...but this formula v=E/density says that velocity is inversely proportional to density!!!!can u pls hlp me out??

 

[Duanoor]

another question when we make a solution of two miscible liquids the boling point of the solution is effected...now ignore that whether it increases or decreases but the whole sol. has a uniform boiling point...if it is so then how we will perform the process of fractional distillation????

 

[Duanoor]

....koi mujhe answer kreeeeee???

 

[smzimran]

Can someone help me with Q 3 c ii?
http://www.xtremepapers.com/CIE/International%20A%20And%20AS%20Level/9702%20-%20Physics/9702_s07_qp_2.pdf

ratio of volumes : ratio of lengths = 3:1
because volume = (length)^3

 

[smzimran]

hey...i did o levels and thn opted for fsc...i am struggling with a question...can u guys hlp me??
we read that in solids speed of sound is greater cz its density is greater...but this formula v=E/density says that velocity is inversely proportional to density!!!!can u pls hlp me out??

What is E?