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Physics: Post your doubts here!

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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:
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.
 
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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.
thanks for explaining but ithink is not in AS course i just wanted to try it :p
 
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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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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 ?
The graph part is crap! -_- I couldn't do it either.
And Thanks:D
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.
Thank you but I already checked the booklet. I was looking for a well organised answer. I kinda suck at these kinda questions:oops:
 
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K.E=(m*(v)^2)/2
K.E=P^2/2m
Since, p=mv so p^2=(mv)^2

K.E= m^2 * v^2/2m
m cancels out in the numerator and the denominator to give m*v^2/2
Hope i Helped :)
 
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w07/2
Q5(c)As stationary wave doesn't travel, the speed calculated is speed of the incident and reflected waves. these two waves superimpose/interfere to create the stationary wave
(d) there is no d part of this question ;)

Q2 (a) electric field strength is the strength of electric field. it can be measured by putting a +ve charge in the field and determine the force it experiences. it is a vector quantity. its formal definition will be "force per unit positive charge in an electric field"

Q(5)(a)
in a transverse wave the particles of medium(like water molecules in water waves) travel perpendicular to the direction in which the energy propagates.
in polarisation we restrict the direction of oscillation of particles in one only one direction which is perpendicular to the direction of propagation of energy.
remind me rest of them tomorrow i am having a severe headache now.
Thank you but can you please properly reply coz i really need help
 
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