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Physics: Post your doubts here!

talha-_-khan

talha-_-khan

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SOME ONE PLEASE EXPLAIN
001.jpg
 
Suchal Riaz

Suchal Riaz

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the resistance will increase. to clear it out why. here is an example:
upload_2014-4-23_4-37-22.png
when resistance decrease current increase as V=IR and V is constant
the P.d around the bulb will be the same. current will be the same though each resistor(overall current will decrease, not in each parallel bulb)
P=IV. as I and V are same, power is same. so the brightness will be the same
another way to look at this question is like this:
upload_2014-4-23_4-45-26.png
 
Malik777

Malik777

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kitkat <3 :p said:
P=W/t or E/T so E=PT => 70*(5*60) => 21000J
for specific latent heat of vapourisation we divide latents heat of vapourisation (i.e. the energy calculated )by mass so
Lf/m= 21000/13.6 = 1544.12 jg^-1
i can be wrong please confirm it :oops:
Click to expand...
you 're wrong :)
Let me tell you the method:

energy given by heater= latent heat of evaporation + heat loss
as heat loss not known thats why he has done the xperiment with two power readings.
what we need to do is to eliminate heat loss by two simultaneous equations by two experiments.
 
K

kitkat <3 :P

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Malik777 said:
you 're wrong :)
Let me tell you the method:

energy given by heater= latent heat of evaporation + heat loss
as heat loss not known thats why he has done the xperiment with two power readings.
what we need to do is to eliminate heat loss by two simultaneous equations by two experiments.
Click to expand...
thanks for explaining but ithink is not in AS course i just wanted to try it :p
 
sweetjinnah

sweetjinnah

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midha.ch said:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s12_qp_41.pdf
question 13 b
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w12_qp_41.pdf
question 10, 11bii, 12b
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w11_qp_41.pdf
10c

Someone please help with these.
Click to expand...
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s12_qp_41.pdf
question 13 b
For this see the Application Booklet..
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w12_qp_41.pdf
question 10, 11bii, 12b
For Q10: Application Booklet.
Q11 bii : 1. Shoter aerial is required.
2. Less attenuation occurs. 3. Less distortion.
 
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S

sitooon

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midha.ch said:
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s12_qp_41.pdf
question 13 b
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w12_qp_41.pdf
question 10, 11bii, 12b
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w11_qp_41.pdf
10c

Someone please help with these.
Click to expand...
Quoted :
11b(ii)
sampling frequency = 44.1 Khz
Since each sample consists of 16- bit word, bit rate(bits per second) = 44.1 x 1000 x 16
Now,
time for recording = (5 x 60) + 40 s = 340 s
number of bits generated in recording time = 340 x bit rate
The writing question , I really memorize them ,

can you draw the graph part in Q9 of same yr ?
 
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