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Edexcel IAL Physics Unit 02- 08 May 2017

Ok I created this thread for the members of TSR doing their exams in May. We can discuss topics and share resources. I'm sorry about the date. It's 8th of May, 2017.

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(edited 7 years ago)

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Sorry you've not had any responses about this. :frown: Are you sure you've posted in the right place? :smile: Here's a link to our subject forum which should help get you more responses if you post there. :redface:


Just quoting in Danny Dorito so she can move the thread if needed :wizard:

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Reply 2
Is it important to know about calculating the phase of a wave in AS?
Anyone please help
Reply 3
Original post by Reshyna
Is it important to know about calculating the phase of a wave in AS?
Anyone please help


I'm guessing only the common phase differences like 90, 180, 270, 360... But it would be wise to check with your teacher. :smile:


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Reply 4
Original post by Droneon
I'm guessing only the common phase differences like 90, 180, 270, 360... But it would be wise to check with your teacher. :smile:


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thanks for saying.
but i'm a private candidate and i'm self-teaching.
Reply 5
Original post by Reshyna
thanks for saying.
but i'm a private candidate and i'm self-teaching.


Oh. Well I haven't come across any such questions, but my teacher did teach us to calculate the phase difference of a wave. No harm if you did know it, though. :smile:


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Reply 6
Could anyone please help me with this question?
Why is the answer for this question, D?
jan 2014 MCQ.png
Original post by Reshyna
Could anyone please help me with this question?
Why is the answer for this question, D?
jan 2014 MCQ.png


This is cosmological shift. The element is usually hydrogen. The image that is shown of it in the lab is used as a reference. So, what you have to do first in underline the part where it says, moving away from Earth (the observer is a better way of saying it). If the star is moving away then the wave-fronts of light are going to spread out more and more, the amount that the wave fronts move depends on the distance of the star and also the speed that it is moving away. So if it is moving away the wavelength increases thus is called red shift. Thus the line spectra will have these black lines (signatures) move towards the red. MAKE SURE THE LINES STAY IN THE SAME PATTERN. SO THE RED SHIFTED PATTERN WILL MATCH THE REFERENCE PATTERN BUT JUST BE SLIGHTLY MORE TOWARDS THE RED. This is why B cannot be the answer. B can easily be eliminated. A shows the pattern flipped and so can also be eliminated. Different patterns are different elements. C shows blue shift which would argue the star is moving towards the observer (earth) which we know is false as it tells us in the question. So your answer is D. If i failed to help you please let me know im happy to explain. I'm a bit rusty on physics not done for a year, but i did the same specification as you.
(edited 7 years ago)
Reply 8
Original post by Konanabanana
This is cosmological shift. The element is usually hydrogen. The image that is shown of it in the lab is used as a reference. So, what you have to do first in underline the part where it says, moving away from Earth (the observer is a better way of saying it). If the star is moving away then the wave-fronts of light are going to spread out more and more, the amount that the wave fronts move depends on the distance of the star and also the speed that it is moving away. So if it is moving away the wavelength increases thus is called red shift. Thus the line spectra will have these black lines (signatures) move towards the red. MAKE SURE THE LINES STAY IN THE SAME PATTERN. SO THE RED SHIFTED PATTERN WILL MATCH THE REFERENCE PATTERN BUT JUST BE SLIGHTLY MORE TOWARDS THE RED. This is why B cannot be the answer. B can easily be eliminated. A shows the pattern flipped and so can also be eliminated. Different patterns are different elements. C shows blue shift which would argue the star is moving towards the observer (earth) which we know is false as it tells us in the question. So your answer is D. If i failed to help you please let me know im happy to explain. I'm a bit rusty on physics not done for a year, but i did the same specification as you.


Thanks a lot. It helped me. The explanation was great! :thumbsup:
Original post by Reshyna
Thanks a lot. It helped me. The explanation was great! :thumbsup:


just from reading before that particular question is a Unit 5 topic which is A2, i doubt they would ask that in As as the As topic is Doppler effect and not cosmological shift. They are extremely similar however just make sure your studying the correct topics or you might get a little bit confused when it comes to the explanation questions.
Hey all!! I am doing AS Physics for the WPH01/02/03 series and some of our spec points like these are required to be learnt. Does anyone have notes for this? Thanks!! 71 explain how wave and photon models have contributed to the understanding of the nature of light 2. explore how science is used by society to make decisions, for example, the viability of solar cells as a replacement for other energy sources, the uses of remote sensing
Original post by theeconomistkid
Hey all!! I am doing AS Physics for the WPH01/02/03 series and some of our spec points like these are required to be learnt. Does anyone have notes for this? Thanks!! 71 explain how wave and photon models have contributed to the understanding of the nature of light 2. explore how science is used by society to make decisions, for example, the viability of solar cells as a replacement for other energy sources, the uses of remote sensing


I an help you if u message me privately some questions u are struggling on
Reply 12
Please, could anyone help me with this question?
The smallest distance between two points on a progressive wave that have a phase difference of 60o is 0.05m. If the frequency of the wave is 500 Hz, what is the speed of the wave, in ms-1 ?
(edited 6 years ago)
Reply 13
Original post by theeconomistkid
Hey all!! I am doing AS Physics for the WPH01/02/03 series and some of our spec points like these are required to be learnt. Does anyone have notes for this? Thanks!! 71 explain how wave and photon models have contributed to the understanding of the nature of light 2. explore how science is used by society to make decisions, for example, the viability of solar cells as a replacement for other energy sources, the uses of remote sensing


Hey
Sorry I read this late. I'm doing the same thing as well, and I'm struggling with WPH03. I've searched notes via internet. But nothing is accurate. So I'm studying the experiments given in the spec.
Reply 14
I came across another question, and it's driving me crazy, I don't have an idea how to do it. It's the 8c. Guys, pls help me...
IMG_20170404_095726.jpg
Original post by Reshyna
I came across another question, and it's driving me crazy, I don't have an idea how to do it. It's the 8c. Guys, pls help me...
IMG_20170404_095726.jpg


That diagram shows a ray of red light entering a raindrop and about to meet the inside edge. You need to work out whether or not the ray of red light will refract out of the raindrop or undergo total internal reflection inside the raindrop. In order to work this out, you need to measure the angle of incidence of the ray of red light with the inside of the raindrop.

In order to do this, you must draw a tangent to the circle at the point where the raindrop meets the inner wall (at the right on the diagram), then use a protractor or set-square to draw in a normal, and then measure the angle from the normal with a protractor. If the angle is greater than the critical angle, the ray will undergo total internal reflection as the raindrop is a denser medium than the air outside. If the measured angle is less than the critical angle, the raindrop will refract out and bend away from the normal.

Note, if the ray does reflect then you should draw the reflected ray at the same angle from the normal, and then show the reflected ray refract out at the other boundary (at the left of diagram).
Reply 16
Original post by K-Man_PhysCheM
That diagram shows a ray of red light entering a raindrop and about to meet the inside edge. You need to work out whether or not the ray of red light will refract out of the raindrop or undergo total internal reflection inside the raindrop. In order to work this out, you need to measure the angle of incidence of the ray of red light with the inside of the raindrop.

In order to do this, you must draw a tangent to the circle at the point where the raindrop meets the inner wall (at the right on the diagram), then use a protractor or set-square to draw in a normal, and then measure the angle from the normal with a protractor. If the angle is greater than the critical angle, the ray will undergo total internal reflection as the raindrop is a denser medium than the air outside. If the measured angle is less than the critical angle, the raindrop will refract out and bend away from the normal.

Note, if the ray does reflect then you should draw the reflected ray at the same angle from the normal, and then show the reflected ray refract out at the other boundary (at the left of diagram).


Thanks a lot. Now I understand that question. If you don't mind, could you please explain this one?

The smallest distance between two points on a progressive wave that have a phase difference of 60o is 0.05m. If the frequency of the wave is 500 Hz, what is the speed of the wave, in ms-1 ?
Original post by Reshyna
Thanks a lot. Now I understand that question. If you don't mind, could you please explain this one?

The smallest distance between two points on a progressive wave that have a phase difference of 60o is 0.05m. If the frequency of the wave is 500 Hz, what is the speed of the wave, in ms-1 ?


A full wave cycle is 360 degrees, and so a full wavelength is the distance between the two closest points with a phase difference of 360 degrees.

What fraction is 60 degrees out of 360 degrees? Hence, work out what fraction of the whole wavelength is 0.05m, and hence work out what the wavelength of the wave is.

Solution (incomplete):

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Then you can use the wave equation v=fλv = f \lambda to solve for wavespeed.
Reply 18
Original post by K-Man_PhysCheM
A full wave cycle is 360 degrees, and so a full wavelength is the distance between the two closest points with a phase difference of 360 degrees.

What fraction is 60 degrees out of 360 degrees? Hence, work out what fraction of the whole wavelength is 0.05m, and hence work out what the wavelength of the wave is.

Solution (incomplete):

Spoiler



Then you can use the wave equation v=fλv = f \lambda to solve for wavespeed.

PRSOM
Thanks a lot!

You are a life-saver!
Hiya! This is a nice exam thread - I've added it to the Exam Thread Directory 2017

If you see any other exam threads threads that aren't in the directory yet - let me know by either tagging me in, or linking it in the directory and I can add it in! You can also find discussions for your other exams there.

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Good luck in your exams

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