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Hi can i know why question 10 the answer is A. How do u do this type of grpahs questions?
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A positively charged oil droplet falls in air in a uniform electric field that is vertically upwards. The droplet has a constant terminal speed v0 and the electric field strength is E.
Physics Reference  ALevel 9702, Past Exam Paper Solutions ..physicsref.blogspot.com
A small charge q is placed in the electric field of a large charge Q.
Both charges experience a force F.
What is the electric field strength of the charge Q at the position of the charge q?
A) F/(Qq)
B) F/Q
C) FqQ
D) F/q
Answer is D, why isn't it B? :O HELP
Hi everyone, AsSalamoAlaikum Wr Wb...
To get things organized in a better way, I am making this thread. As othewise, some queries remain unanswered!
So post your PHYSICS doubts in this thread. InshaAllah other people here will help me and you all.
NOTE: If any doubts in the pastpapers, please post the link! You can find links here!
Any Physics related notes and links will be added here in this post. Feel free to provide the links to your notes around the forum, or any other websites!
Thanks!
Jazak Allah Khair!
Physics Notes:
Some links & Notes  by destined007
As physics p1 MCQS YEARLY Solved [explaination]
Physics Practical Tips  by arlery
Notes for A2 Direct Sensing (Applications)  shared by sweetiepie
Physics Summarised Notes (Click to download)
AS and ALevel Physics Definitions
A2: Physics Revision notes  by smzimran
Paper:5 Finding uncerainty in log  by XPFMember
Physics Paper 5 tips  by arlery
Physics Compiled Pastpapers: <Credits to CaptainDanger for sharing this..>
Here are the compiled A level topical Physics questions in PDF form...
Paper 1 : http://www.mediafire.com/?tocg6ha6ihkwd
Paper 2 & Paper 4 : http://www.mediafire.com/?g65j51stacmy33c
(Source : http://www.alevelforum.com/viewtopic.php?f=15&t=14)
It is because the charge is constant but the potential is changing which means you've got to integrate the dE = QdV expression over the given limits of V1 and V2. Since the 1/2 factor is only introduced due to integration, therefore this gives the right answer. The formula (change in V) = E/Q doesn't have the 1/2 factor in it so you can't get the correct answer because of it.View attachment 65745
in the last part why cant we find the work done using change in potential=workdone/charge. and since workdone is the change in energy it should be valid right? it doesnt give the right answer.
To answer this question, you need to consider the free body diagrams (ignoring trolley weight of course) before and after the displacement of trolley. The right side can be considered as positive for force and displacement direction and vice versa. So initially the forces from both springs act in opposite directions in equal magnitude, thus keeping the trolley in equilibrium, i.e. F = ke.View attachment 65741can anyone explain Q11 (b) (i)? I read an explanation somehwere and it said that the two forces have to be subtracted because they are opposite in direction. Why subtract when both forces are in same direction? Shouldn't we add? Both springs will exert a force to the left to bring it to the equilibrium position right?
but the potential needs to be changing; we need to have two values of potential to get potential difference which is exactly what was given. What i have figured is that the charge is what's changing cuz in one of the earlier parts of question it says charge required to raise sphere to a potential, so when the potential drops, sphere loses some of its charge in the spark so we cant use potential difference=workdone/charge cuz its the charge that doesnt stay constant. for potential difference we need to two different values. so I found the energy using different potential and charge values at both points and substracted them to get the loss in the energy and it was correct.It is because the charge is constant but the potential is changing which means you've got to integrate the dE = QdV expression over the given limits of V1 and V2. Since the 1/2 factor is only introduced due to integration, therefore this gives the right answer. The formula (change in V) = E/Q doesn't have the 1/2 factor in it so you can't get the correct answer because of it.
yeah that is understandable...totally makes sense.but the potential needs to be changing; we need to have two values of potential to get potential difference which is exactly what was given. What i have figured is that the charge is what's changing cuz in one of the earlier parts of question it says charge required to raise sphere to a potential, so when the potential drops, sphere loses some of its charge in the spark so we cant use potential difference=workdone/charge cuz its the charge that doesnt stay constant. for potential difference we need to two different values. so I found the energy using different potential and charge values at both points and substracted them to get the loss in the energy and it was correct.
Q25/. The distance between a node and an antinode is wavelength/4 meters. the frequency of this note is 75 hertz. v= frequency x wavelength. So, the frequency is equal to 75 = v/4L where L is the distance between a node and an adjacent antinode. L=wavelength /4. Wavelength = 4L. The v of the stationary wave is the same. Thus, the length of the tube in the second higher note will be 3 x wavelength / 4. 4L=3 x wavelength. wavelength = 4L/3. So, the frequency is equal to = 3v/4L = 3 x. (v/4L) = 3x 75 = 225 Hz. DO the same for the third higher note. And the answer will be D.Re: Physics Help here! Stuck somewhere?? Ask here!
Problems in june 2011 paper 11
No 25, 27, 29, 32, 35,, 36,37..
And also can u send me some notes on potential divider, internal resistance along with some working examples which cover the whole chapter...
Thnks in adv..
Bro the 2021 papers will come out exactly when the Indian student's AS and A level receives their grades from Cambridge. Idk what date is that on tho. SO,...if anyone has the Feb/March 2021 papers for physics please send them to me!! it would be greatly appreciated
Actually they get leaked after they take their exam since sometimes leftover exam copies are kept by their teachers and they give it to their students. I came across the math papers for feb/march 2021 already somewhere.Bro the 2021 papers will come out exactly when the Indian student's AS and A level receives their grades from Cambridge. Idk what date is that on tho. SO,...
when do their exam results come out?Bro the 2021 papers will come out exactly when the Indian student's AS and A level receives their grades from Cambridge. Idk what date is that on tho. SO,...