Physics: Post your doubts here!

[Omar99]

for no. 40 nucleus x is emitting an alpha particle so 84-2=82
then it gains two beta particles so 82+2=84

ok but what about neutron no.

 

[InternationationalGuy]

Hey guys. Hope you all are doing fine studying. I wanted to ask what equipment are we to bring when doing the practical of physics and what things will be provided. Thanks.

 

[Omar99]

can some one tell me question no. 7 part a and c and question no.9 part c
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w11_qp_42.pdf

 

[dhahir23]

How to find uncertainty in logs?
http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_w07_qp_5.pdf

Q 2(b)

 

[Princess Raven]

guys may june 2012 v32 q 11 CAN SOMEONE PLZ EXPLAIN???!!!

 

[salvatore]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s07_qp_2.pdf
Please help me with qn. no 3 c (i & ii).. seems pretty easy but I just can't solve it.
Thanks

 

[gary221]

How to find uncertainty in logs?

Q 2(b)

uncertainty in I = [log(I + error in I) - log(I - error in I)] / 2

 

[aleezay]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s03_qp_1.pdf
Please help me out with Q20 asap. The answer is A.. :/

 

[Malik777]

Any One Plz Tell me What is Phase difference & Path difference?

 

[salvatore]

Any One Plz Tell me What is Phase difference & Path difference?

Path difference is simply the difference in the distances travelled by two waves from coherent sources at a particular point. In other words, it is the difference (in meters) between the lengths of two paths.

Phase difference is a little complicated.. but hope the following explanation will make it clear.
In periodic phenomena, the phase is the relative position in the cycle. That is if you divide all the cycle in 360 degrees (or better in 2 pi radians), and decide to start counting at a given position, each time that the process attains the same position its phase will have advanced 360 degrees.
Take an example of a walking person, and place the start of phase when the right foot touches the earth. When the phase advances 180°, the left foot touches the earth. See why?
Now take two persons walking beside. They start touching the earth with their right foot simultaneously: they are in phase, their phase difference is zero.
If they are parading soldiers they will stay in phase and their right foots will continue to touch the earth simultaneously.
But if they are not parading, the phase difference of each one will be probably different. If the period of person B is shorter, his right foot will touch earth a little before person A. We say that person B is in advance on phase relative to A, or that the phase of A lags B.
When two waves have the same periodicity i.e same frequency, and travel at the same speed and same distance, they will have the same phase difference.

 

[ahmed abdulla]

can any one help with drawing traingle vector and finding area of non-staright line
q 2(c) and q 3(i) .... i cannot post the link for this year ... it gets stuck ....! its m'j 2010 varient 23

Tkp syed1995

 

[Tkp]

for 3a my ans is 36 and the ms shows 39

can any one help with drawing traingle vector and finding area of non-staright line
q 2(c) and q 3(i) .... i cannot post the link for this year ... it gets stuck ....! its m'j 2010 varient 23

Tkp syed1995

 

[ahmed abdulla]

for 3a my ans is 36 and the ms shows 39

what about others ... also how to draw if thhey said path difference is 90 degree

 

[1357913579]

can someone please help
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_41.pdf
6b(ii)
please explain this iam totally stuck at this.
Jazak Allah khair

 

[Minato112]

can any one help with drawing traingle vector and finding area of non-staright line
q 2(c) and q 3(i) .... i cannot post the link for this year ... it gets stuck ....! its m'j 2010 varient 23

Tkp syed1995

Question 2 (c) attached!

For the 3 (i), there's only one way. Split the graph into 3 parts minimum and calculate the area under graph. I believe cambridge have a range of values of the distance moved.

 

[gary221]

can someone please help
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_s11_qp_41.pdf
6b(ii)
please explain this iam totally stuck at this.
Jazak Allah khair

magnetic flux proportional to emf in primary coil {the emf in d primary coil will induce a mag field ie mag flux (as d field cuts d wire)}
emf across secondary proportional to rate of change of magnetic flux [this changing mag flux, according to faraday's law will induce an emf in d secondary coil... thus, emf in d secondary coil is proportional to d RATE of changing flux]
so emf of supply not in phase with pd across secondary.

 

[gary221]

can some one tell me question no. 7 part a and c and question no.9 part c
http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w11_qp_42.pdf

For 9 c)... calculat value of V(out) for 5 values of Vin (0, 0.2, 0.4, 0.6, 0.8, 1) using d formula Gain = Vout/Vin. So, Vout = Vin * Gain (whr Gain = 15)
So Vin = 0 V, Vout = 0 V
Vin = 0.2 V, Vout = 3 V
Vin = 0.4 V, Vout = 6 V
Vin = 0.6 V, Vout = 9 V
Vin = 0.8 V, Vout = 9 V (although Vout should be equal to 12V, d op-amp will be saturated at 9 V, so Vout cannot exceed 9 V)
Vin = 1 V, Vout = 9 V
and plot the pts in d graph...

 

[xxxt]

does any one know the explanation for the gap in the stress-strain graph of a polythene?

 

[ahmed abdulla]

Question 2 (c) attached!

For the 3 (i), there's only one way. Split the graph into 3 parts minimum and calculate the area under graph. I believe cambridge have a range of values of the distance moved.

did u now that ur great ??? $#$#$#$#$#$

 

[Minato112]

did u now that ur great ??? $#$#$#$#$#$

Haha! Glad it helped!