A2 Physics | Post your doubts here

[angelicsuccubus]

you are absolutely right that it provides evidence for particulate nature of light.
but are you sure it doesnt show the particulate nature of electrons too?
For example if there is a question that asks to design an experiment to prove particulate nature of electrons, What experiment do we draw?

Wikipedia :- "The photoelectric effect requires photons with energies from a few electronvolts to over 1 MeV in high atomic number elements. Study of the photoelectric effect led to important steps in understanding the quantum nature of light and electrons and influenced the formation of the concept of wave–particle duality"

Are you sure electrons are not proven as particles from the photoelectric effect?

okay first of all.. we study wave-particle duality in our syllabus which is about light. That's it. Just how light acts as a wave and a particle.

but.. Experiments with a Crookes tube first demonstrated the particle nature of electrons. And the wave nature of electrons comes from the De Broglie hypothesis.

 

[optimistic]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_42.pdf
can anyone explain me Q1b(iii)?

 

[SkyPilotage]

The emf and current in the primary coil of a transformer are in phase right?

 

[Inert.Phantom]

GUys pLz help me ... I M unable to draw A relay circuit... can any1 draw it ?

 

[SkyPilotage]

okay first of all.. we study wave-particle duality in our syllabus which is about light. That's it. Just how light acts as a wave and a particle.

but.. Experiments with a Crookes tube first demonstrated the particle nature of electrons. And the wave nature of electrons comes from the De Broglie hypothesis.

Yes, thats what I found too. That means they wont ask us for an experiment for particle nature of electrons, and may you please confirm that the milikan's experiment does not show evidence for particulate nature of electrons i.e just quantisation of chare?
Please be informed that the diagram for the wave nature of electrons is included in our syllabus, where it is diffracted by a carbon film to form concentric circles.

 

[user]

assalamoalaikum wr wb!

is this correct...the second one..? [first one is from the booklet..]

​

 

[SkyPilotage]

An increease in electric potential of particles does not necessarily mean increase in volume i.e work done by gas, right?
Evidence of this is that ideal gas exert work on atmosphere but have no electric potential energies.

 

[SkyPilotage]

assalamoalaikum wr wb!

is this correct...the second one..? [first one is from the booklet..]

View attachment 9358​

same thing, a longer piece of wire wont make a difference.

 

[user]

same thing, a longer piece of wire wont make a difference.

not abt the longer piece....being connected to earth was all i was confused abt

 

[SkyPilotage]

GUys pLz help me ... I M unable to draw A relay circuit... can any1 draw it ?

assalamoalaikum wr wb!

is this correct...the second one..? [first one is from the booklet..]

View attachment 9358​

Thats what I call, a question answering another question!

 

[SkyPilotage]

not abt the longer piece....being connected to earth was all i was confused abt

both are connected to earth.

P.S:- 0v and earth are same thing

 

[user]

Thats what I call, a question answering another question!

 

[user]

GUys pLz help me ... I M unable to draw A relay circuit... can any1 draw it ?

assalamoalaikum wr wb!

[first one is from the booklet.. and second one is a pastpaper question...if you're referring to that one ... ]

 

[Inert.Phantom]

GUys tis is like a simple circuit of relay...? where is the coil for induction...?

 

[Inert.Phantom]

JUNE.. 10 Q 10

 

[user]

brother i want ot discuss wid u diodes graph.......i am not crystal clear abt them

Check this link: http://www.flashscience.com/electricity/smoothing.htm
It'll help you..! it's perfect i feel
and btw for that graph question, which skypilotage told that u were wrong about, check posts from here:
http://www.xtremepapers.com/communi...st-your-doubts-here.13317/page-37#post-231941
http://www.xtremepapers.com/communi...st-your-doubts-here.13317/page-37#post-231953
http://www.xtremepapers.com/communi...st-your-doubts-here.13317/page-38#post-231997

 

[smzimran]

well no need to knw the derivcation of eq...1/3 *density*c^2

You need to know that i think.
I think it was there in the revision checklist!

 

[hassam]

The question clearly asks for mean power so the Irms current should be used in the calculations and not the peak current as they have done in ms.

ohh k

 

[optimistic]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s10_qp_42.pdf
can anyone explain me Q1b(iii)? PLEASE HELPPPP!

 

[angelicsuccubus]

Yes, thats what I found too. That means they wont ask us for an experiment for particle nature of electrons, and may you please confirm that the milikan's experiment does not show evidence for particulate nature of electrons i.e just quantisation of chare?
Please be informed that the diagram for the wave nature of electrons is included in our syllabus, where it is diffracted by a carbon film to form concentric circles.

ofo... electron's nature was already considered a particle. kay? Then de broglie was thinking about how light which is considered a wave has a particle nature.. so then he thought maybe things like electrons which are considered particles would have a wave nature.

And no, the only thing milikan did was find the size of the charge on the electron. ... o0h I haven't seen that diagram... so when I come across I'll reply again to clarify this whole electron's nature crap.