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A2 Physics | Post your doubts here

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How to convert analogue instantaneous or sample voltage into a binary number?
 
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How to convert analogue instantaneous or sample voltage into a binary number?
A Analogue to digital converter is used where samples are taken at certain intervals of time i.e sampling rates to convert the decimal number into binary digits made of a certain number of bits.
2^3 / 2^2 / 2^1 / 2^0
8 4 2 1
Example 9 is 8 + 1 so the binary digit is
1 0 0 1
Hope you got it :)
 
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i asked across diode!!!
Then just flip your monitor upside down :p
If voltage across resistor is increasing, voltage across diode is decreasing and vice versa. When voltage across R is Max , voltage across diode is zero and vice versa again!
Kirchoff's Voltage Law!
 
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please make some brief elaboration on the first part of the emf of the graph... why is it somehow as a sine graph rather than a cosine graph? why couldnt it be a straight line sloping downwards?
How do we know if the rate of decrease is constant or the rate of decrease is increasing/decreasing? Will appreciate some interpretation :)
The shape of magnetic flux graph would be same as the shape of current graph. So, at first, the gradient is maximum and positive giving rise to a large negative emf - the gradient decreases to zero in the end of first part, so the emf goes from that max. value to zero. You can't draw a straight line because then you can't show that the decrease to zero is gradual.
 
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The shape of magnetic flux graph would be same as the shape of current graph. So, at first, the gradient is maximum and positive giving rise to a large negative emf - the gradient decreases to zero in the end of first part, so the emf goes from that max. value to zero. You can't draw a straight line because then you can't show that the decrease to zero is gradual.
Have some problems getting this clear... The gradient of the current graph looks undefined at the beginning? tangent to that point is vertical? means emf shouldnt touch the axis?
 
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Describe how you would demonstrate the photoelectric effect. Include a diagram of the
apparatus........cud come cos electron diffraction and lenzs law has come already
by the way is stopping potentail in syllabus
 
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Have some problems getting this clear... The gradient of the current graph looks undefined at the beginning? tangent to that point is vertical? means emf shouldnt touch the axis?
Slightly less than vertical, which means that there's a large emf. My diagram shows both graphs being compared. See it again with the explanation I gave above.
0-magemf.png
 
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Slightly less than vertical, which means that there's a large emf. My diagram shows both graphs being compared. See it again with the explanation I gave above.
View attachment 9017
thats the problem , i cant seem to agree with your explanation.
Because I am reluctant why it cant be somehow convex rather than concave. Meaning it should be like the shape of an alternating voltage i.e how did you the rate of decrease of current decreases rather than increase with time!
 
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thats the problem , i cant seem to agree with your explanation.
Because I am reluctant why it cant be somehow convex rather than concave. Meaning it should be like the shape of an alternating voltage i.e how did you the rate of decrease of current decreases rather than increase with time!
yeah i also dont agree with the explanation......
 
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thats the problem , i cant seem to agree with your explanation.
Because I am reluctant why it cant be somehow convex rather than concave. Meaning it should be like the shape of an alternating voltage i.e how did you the rate of decrease of current decreases rather than increase with time!
If you see the graph of current, you will see that current becomes constant just a little time before the start of the second phase. You need to show that the emf goes from a specific maximum value to zero - you can't show it the other way round. I really feel there is no more to say here.
 
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If you see the graph of current, you will see that current becomes constant just a little time before the start of the second phase. You need to show that the emf goes from a specific maximum value to zero - you can't show it the other way round. I really feel there is no more to say here.
You seem very confident, yet having problems interpreting the problem :D
Can you continue your curve if current has not been switched off? Current would be sinosoidal and EMF too! but with a 90 degree phsa shift.
Transformers always output an alternating e.m.f , but you sketch does not show any form of sinosoidal wave. I am even curious to know about its Period or wavelength :rolleyes:
Meh, anyways , Thank you for your time in this matter and constant reply!!! (y)
I would appreciate it if someone could join the discussion and clarify the question ;)
 
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Slightly less than vertical, which means that there's a large emf. My diagram shows both graphs being compared. See it again with the explanation I gave above.
View attachment 9017

ok a simple question distrubing me..
when the current is increasing from zero and moving towards the max. of curent aftr which the graph is still with no increase in current aftr it.


wel fr that time emf is increasing bt is increasing in in neagitve axis!!1
why nt in positive axis??

hope u gt what i am tryng to say:unsure:
 
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