Physics: Post your doubts here!

[Thought blocker]

thank u very much but i dont think i asked abt the current question. the actual question is question 6b) from :
papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w07_qp_2.pdf

thanks in advance. Suchal Riaz

bi)
V= 230 -225 = 5
R=V/I =0.11ohm

bii)rho = 1.8*10^-8,Length = 16, Resistance = 0.11
R=rho*L/A
0.11=(1.8*10^-8*32)/A
A=5.3*10^-6 m^2

 

[Thought blocker]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_qp_21.pdf
"Q6(ii) " sketch would be appreciated

Not sure. Suchal Riaz ZaqZainab usama321
Well is a st line till 3A and 12 V and then curve.

 

[usama321]

Not sure. Suchal Riaz ZaqZainab usama321
Well is a st line till 3A and 12 V and then curve.View attachment 39465

Straight line at start, and then curves downwards... but NEVER horizontal

 

[sara kamal]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_41.pdf @ ninjaln Pyjamas,usama321,biscuitbiscuit,Mohammmed salik

please explain Q10 c 2
and Q9 b2

 

[Suchal Riaz]

Not sure. Suchal Riaz ZaqZainab usama321
Well is a st line till 3A and 12 V and then curve.View attachment 39465

 

[Thought blocker]

Sure :
5a)
its easier if u convert the angle in radian ie multiply by (π/180°) ----> 60° = π/3 rads.
n c this --->
thts whr the new wave will start!

So it would look like :

Correct me if it is wrong. ZaqZainab Suchal Riaz

Suchal Riaz is this correct ?

 

[biscuitbiscuit]

Straight line at start, and then curves downwards... but NEVER horizontal

Hey can you please explain Q6(c) also

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w10_qp_22.pdf

 

[biscuitbiscuit]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_41.pdf @ ninjaln Pyjamas,usama321,biscuitbiscuit,Mohammmed salik

please explain Q10 c 2
and Q9 b2

Still in As, maybe next year

 

[Fahm Deen]

Oct/Nov 2010/21 Question-6.b . Please give me a solution with complete explanation.

 

[sitooon]

MS :
force on mass = mg (where g is the acceleration of free fall
/gravitational field strength)
g = GM/r^2
if r @ h, g is constant
ΔEP = force × distance moved
= mgh

 

[chocolate_girl]

16:
B is incorrect because the velocity does not decrease uniformly (it's roughly parabolic), which means height of the ball does not increase uniformly, which means the potential energy of the ball does not increase uniformly (since Ep = mgh and rate of h is not constant).
26:
HOPE IT HELPS

Emm i dont find any explanation for 26 but thanks for helping with 16

 

[Suchal Riaz]

Emm i dont find any explanation for 26 but thanks for helping with 16

-->Intensity is directly propotional to square of a
it means if A in two times, I is four times
-->Intensity is inversely proportional to area
by first rule and second rule, E increase 4 times due to doubling of A but decreases 1/2 times due to halving of area. so E(new) = E*4/2=2E

 

[Suchal Riaz]

View attachment 39472

MS :
force on mass = mg (where g is the acceleration of free fall
/gravitational field strength)
g = GM/r^2
if r @ h, g is constant
ΔEP = force × distance moved
= mgh

change in U = Work done against weight
= F.s = W.h=m.g.h

 

[Suchal Riaz]

Hey can you please explain Q6(c) also

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_qp_22.pdf

okay so the range is from 1.5 to 3.5 V for 0-25 C
Volt meter reads only upto one decimal place, 0.1 V. 0.1V/1V * 25 C = 2.5 C. it means that the temperature can be known close to 2.5 C of the real values.
and secondly the circuit has another problem. the line is not straight. so same change for temperature is not same change for voltage for all values. it changes.

 

[Suchal Riaz]

Sure :
5a)
its easier if u convert the angle in radian ie multiply by (π/180°) ----> 60° = π/3 rads.
n c this --->
thts whr the new wave will start!

So it would look like :

Correct me if it is wrong. ZaqZainab Suchal Riaz

its correct.
the new wave will have phase difference of 60 degree. which means that 1/6 of the one wavelength. which means one big block of 10 small blocks.
and the new amplitude will be √(2) of A.
which is almost 0.7a

 

[Snow Angel]

bi)
V= 230 -225 = 5
R=V/I =0.11ohm

bii)rho = 1.8*10^-8,Length = 16, Resistance = 0.11
R=rho*L/A
0.11=(1.8*10^-8*32)/A
A=5.3*10^-6 m^2

yes , but how is this ans the area of one of the wires. should nt we halve this answer?

 

[usama321]

View attachment 39471

It should be a straight line till at least 1.5A. V and I are directly proportional at lower temperatures. Straight at start, and curved at end, that's what the ms usually says

 

[Thought blocker]

yes , but how is this ans the area of one of the wires. should nt we halve this answer?

Suchal Riaz My teacher had not teach me anytime to half. Do we have to half ? :'(

 

[biscuitbiscuit]

okay so the range is from 1.5 to 3.5 V for 0-25 C
Volt meter reads only upto one decimal place, 0.1 V. 0.1V/1V * 25 C = 2.5 C. it means that the temperature can be known close to 2.5 C of the real values.
and secondly the circuit has another problem. the line is not straight. so same change for temperature is not same change for voltage for all values. it changes.

I didn't get this thing, did u mean 1.5 to 3.5 ohms if not how did you get volts?

 

[itallion stallion]

Plz help me with May June 2013 paper 41 question 5 part cii and question 11 part biii.
Thanks a lot!