A2 Physics | Post your doubts here

[Zishi]

...

Presuming that's the question about determining resistivity of glass or any metal block. That's wrong. You can't use crocodile clips - you've to use metal plates that will act as electrodes.

 

[angelgirl:)]

can u explain how the resonant frequency can be found by using the apparatus you've shown?

hmmm ok...
the dependent variable is the resonent "f" and the independent var. is the volume of air in the bottle. the height of the bottle can be varied but the radius kept constant. V=pie*r^2*h is used. The signal generator is set at a specific "f" and the 'f' varied untill the oscillations of the bottle r observed to be at a max. That value of 'f' is recorded. The bottle should be of same radius, 'f'' and thickness. tThe diameter is more accurate to measure and can be d/2=r. safty screen and goggles can be used in case the bottle breaks. The apparatus is given time b/w readings to cool. Agrafh of 'f^2' (y-axis) against 1/v (x-axis) is plotted and if its straight line that passes through origin , the theroy is proved...gradient of line = k..switch off power supply when not in use. Use sound observations/mic and oscilloscope screen and see max. amplitude rather than vibration observation and use a quite room.....
hope u get it...

 

[angelgirl:)]

Presuming that's the question about determining resistivity of glass or any metal block. That's wrong. You can't use crocodile clips - you've to use metal plates that will act as electrodes.

but then how u will connect to the circuit ...the metal blocks or glass sheet with the help of metal plates...cud u plz show me the diagram?

 

[Zishi]

but then how u will connect to the circuit...

The metal plates can be connected to the circuit by wires.

 

[smzimran]

If you use an ohm-meter, there shouldnt be a power supply!
Check the m.s

 

[angelgirl:)]

The metal plates can be connected to the circuit by wires.

hmm ok...thanks

 

[angelgirl:)]

If you use an ohm-meter, there shouldnt be a power supply!
Check the m.s

then how u will gain resistance value/

 

[smzimran]

The ohm meter measures it without power supply!
The second procedure is that connect a power supply, and an ammeter in series and a voltmeter in parallel.
The resistence R = voltmeter reading / ammeter reading

 

[angelgirl:)]

The ohm meter measures it without power supply!
The second procedure is that connect a power supply, and an ammeter in series and a voltmeter in parallel.
The resistence R = voltmeter reading / ammeter reading

ohhhhhhhhh..ok thanks...

 

[alphabravocharlie]

precedure write by yourself after looking at this diagram..

Use a tuning fork on the glass for resonance.

JazakAllah

 

[alphabravocharlie]

guys i cant find the errors in v^2.can anyone help me and tell me the calculations and answers....
secondly it it necessary for the worst acceptable line to pass through all the error bars.?what if it doesnt??????
and thirdly i cant find the examiner report for this particular paper.can any1 post the link to it
thanx in advance

 

[maleeha123]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w09_qp_52.pdf
how to find uncertainity in t^2/s^2 in Q2

 

[tasnim007]

precedure write by yourself after looking at this diagram..

Isn't this question talking about the resonance frequency of the volume of air in the bottle or whatever container?

 

[mr_perfect]

Hello there.
When we make a graph in our P5, there is always a question about calculating the Gradient.
When we calculate the gradient we have to show the 'Gradient-Triangle' which has its own marks.

The question is, when calculating uncertainty in gradient we subtract the gradient of Best fit and Worst fit. Do we have to show the 'Triangle' for the Worst fit line?

YES MY PAL U HRAVE TO

 

[angelgirl:)]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w09_qp_52.pdf
how to find uncertainity in t^2/s^2 in Q2

for the first value...
0.36^2-0.34^2/2=0.007

 

[angelgirl:)]

Isn't this question talking about the resonance frequency of the volume of air in the bottle or whatever container?

wat ever container...but it should be closed...

 

[tasnim007]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w09_qp_52.pdf
how to find uncertainity in t^2/s^2 in Q2

Subtract min. possible value of t^2 ((t-0.01)^2) from max. possible value of t^2 ((t+0.01)^2), Then divide by two.
(((t+0.01)^2)-((t-0.01)^2))/2

 

[tasnim007]

wat ever container...but it should be closed...

thanks..i was just wondering if you were talking about the resonance of the container.

 

[Aqsa Mohd]

that u have to decide and plus some kind of arrangement will be given sometimes...so u will get some idea about it...for those type u just have to modyfy tha diagram...

ok thanks .. but still im very nervoues abt p5. can i have an upload of ur may june 2010 p51. plz

 

[mr_perfect]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_51.pdf
What will be the diagram and procedure for this?

LOUDSPEAKER CONNECTED TO A VARIABLE FREQUENCY GENERATOR TO VARY FREQUENCY . EACH TIME FREQUENCY IS VARIED A NEW MAXIMUM IS OBTAINED. MAXIMUM AMPLITUDE IS MEASURED USING MICROPHONE CONNECTED TO A C.R.O. HOPE IT HELPED INSHA-ALLAH U WILL ACE 2MORO'S XAM