• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

A2 Physics | Post your doubts here

A

Abdulrab

Messages
155
Reaction score
5
Points
28
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s07_qp_4.pdf kindly give me the answer for
Q 2 c )ii) how can the calculated heat capacity smaller than the correct value. please i need a valid reason i think it should be greater than the correct value.
Q4 c(ii) kindly sketch the graph for this question.
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_w07_qp_4.pdf
Q 4c (ii)
Q 6 b (ii)

Thanku im waiting for conceptual and clear answers soon

Thanks again in advance
 
S

SkyPilotage

Messages
265
Reaction score
89
Points
28
When
smzimran said:
Bro can you check out june 2009 / p4
Q11 part(b) (iii)
Click to expand...

From Part ii) The Intensity that reaches the surface of the bone i.e the muscle bone boundary is 0.389! Hence the Intensity is 0.389I. This means that 0.661 has been reflected and 0.389 has been transmitted.

From Part i) The Intensity that is reflected back from the muscle bone boundary is 0.331 i.e 0.331 x 0.389 I

The key to this part is that you have to deduce the Intersity reflection coefficient from part ii).
When the ultrasound reaches the surface of the muscle, 0.661 will be reflected and 0.389 will pass through ----> 0.331 x 0.389 x 0.389 I = 0.05 I
 
S

SkyPilotage

Messages
265
Reaction score
89
Points
28
Q
Abdulrab said:
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s07_qp_4.pdf kindly give me the answer for
Q 2 c )ii) how can the calculated heat capacity smaller than the correct value. please i need a valid reason i think it should be greater than the correct value.
Q4 c(ii) kindly sketch the graph for this question.
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w07_qp_4.pdf
Q 4c (ii)
Q 6 b (ii)

Thanku im waiting for conceptual and clear answers soon

Thanks again in advance
Click to expand...
June 2007
Question 2 c ii)
In calculation L = Q( from heater ) / Mass
In real life L = Q(from heater + surroundings ) / Mass <----- This is the True / Correct Value for L!
I think you can figure it out from here
Question 4 c ii)
Please Find in attachment.
 

Attachments

  • 08052012096.jpg
    08052012096.jpg
    537.5 KB · Views: 19
S

SkyPilotage

Messages
265
Reaction score
89
Points
28
Aahliya said:
can anyone explain me this question.. ??
M/J 2006
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)
Q1 (c) The total energy of the satellite gradually decreases.
State and explain the effect of this decrease on
(i) the radius r of the orbit,

(ii) the linear speed v of the satellite.
Click to expand...
You need to solve part b correctly first.
Total energy of satellite is negative.If it decreases, this means that it is becoming more negative, meaning that the numerical value of energy is increasing hence from the formula r decreases.
When r decreases, the kinetic energy value will increase which means that the speed v will increase too since k.e is proportional to speed = 1/2 mv^2.
 
A

Abdulrab

Messages
155
Reaction score
5
Points
28
SkyPilotage said:
Q

June 2007
Question 2 c ii)
In calculation L = Q( from heater ) / Mass
In real life L = Q(from heater + surroundings ) / Mass <----- This is the True / Correct Value for L!
I think you can figure it out from here
Question 4 c ii)
Please Find in attachment.
Click to expand...


thanku sir but i8 want to ask as the heat from surrounding is also absorbed during the experiment so it means more ice will melt and the mass of water in the hollow will be greater so it means that the correct value should be lesser than the calculated value !! is nt it right ???? please correct me if i am wrong
 
A

Abdulrab

Messages
155
Reaction score
5
Points
28
Abdulrab said:
thanku sir but i8 want to ask as the heat from surrounding is also absorbed during the experiment so it means more ice will melt and the mass of water in the hollow will be greater so it means that the correct value should be lesser than the calculated value !! is nt it right ???? please correct me if i am wrong
Click to expand...
and also solve nov 07 questions. thanku
 
princesskt

princesskt

Messages
96
Reaction score
16
Points
8
SkyPilotage said:
You need to solve part b correctly first.
Total energy of satellite is negative.If it decreases, this means that it is becoming more negative, meaning that the numerical value of energy is increasing hence from the formula r decreases.
When r decreases, the kinetic energy value will increase which means that the speed v will increase too since k.e is proportional to speed = 1/2 mv^2.
Click to expand...
BRO PLEASE DOONE Q 10 C(II) NEED A GOOD EXPLANATION.............. THIShttp://www.xtremepapers.com/papers/CIE/Cambridge%20International%20A%20and%20AS%20Level/Physics%20(9702)/9702_s11_qp_41.pdf
 
S

SkyPilotage

Messages
265
Reaction score
89
Points
28
Aahliya said:
M/J 2006 Q3 (c)

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s06_qp_4.pdf

Solve this one... pls :)
Click to expand...
There is no part c :eek:
Abdulrab said:
thanku sir but i8 want to ask as the heat from surrounding is also absorbed during the experiment so it means more ice will melt and the mass of water in the hollow will be greater so it means that the correct value should be lesser than the calculated value !! is nt it right ???? please correct me if i am wrong
Click to expand...
No! When we calculate .. The heat from atmosphere is NOT taken into account, which is why Q in calculations is lower than the true value! Hope you got it...
Unless someone does, will solve it tmrw morning hopefully.
 
Aahliya

Aahliya

Messages
57
Reaction score
3
Points
8
SkyPilotage said:
There is no part c :eek:

No! When we calculate .. The heat from atmosphere is NOT taken into account, which is why Q in calculations is lower than the true value! Hope you got it...
Unless someone does, will solve it tmrw morning hopefully.
Click to expand...
hey i mean part b
 
H

hassam

Messages
2,619
Reaction score
293
Points
93
well Steps to obtain emission line spectrum:
  • Gases such as hydrogen or neon are placed in an discharge tube at low pressure.
  • A high voltage of several kilo-volts is applied across the cathode and anode of the discharge tube.
  • The gas atoms become excited by the collision with the electrons passing through the tube.
  • When the gas atoms fall to a lower energy level, the excess energy is emitted as electromagnetic radiation(photon) with a specific frequency. The frequency f of the emission line is dependent on the difference between the high and low energy levels. ΔE = hf
  • Only certain frequency lines are present in the spectrum as only certain high to low energy level transitions are possible within the atom.
The emitted light are analyzed with a spectrometer and discrete bright lines in a dark background are observed
well sources say that low pressure must be used.....with high pressure u cant get lines.......thatys what chris mee says....bt chadha says no high pressure....??
 
princesskt

princesskt

Messages
96
Reaction score
16
Points
8
how to find area in ques 3 (b) by conting no of boxes takes a lot of time.........
 

Attachments

  • 9702_s07_qp_4 (1).pdf
    322.3 KB · Views: 2
You must log in or register to reply here.
Top