AQA Physics: PHYA1 Tuesday 19th May 2015 (AM) and PHYA2 Thursday 04th June 2015 (PM)x

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I dont even think we need to know exchange particle, just that it affects hadrons only

Yeah ok, so we will never have an equation that uses the S.N.F and we have to fill in particles that are missing? just on the weak nuclear force?

Reply 981

the_german_boy

Original post by a.a.k

Posted from TSR Mobile

Yeah just ignore what he said...it's true but we don't need to know it yet. Just always say it's a gluon

Reply 982

KayJuanito

Original post by a.a.k

Posted from TSR Mobile

Thats not the spec
11289643_840036419412244_2013805740_n (3).jpg

Reply 983

Slenderman

Original post by KayJuanito

pion0 between nucleons, gluon between quarks
but gluon not in spec

What are you talking about? It's gluon and it is in our spec.

Reply 984

A*da*m

Original post by Mina Makin

yh a positron. Thanks a lot mate!

That's okay :smile:

If you have any other questions just quote or pm me :smile:

Reply 985

a.a.k

Original post by KayJuanito

Thats not the spec
11289643_840036419412244_2013805740_n (3).jpg

Thanks man. And its ood thing coz i dont have to learn it :hand:

Posted from TSR Mobile

Reply 986

tanyapotter

how likely do you think it is that we'll get asked a question on the starter unit of a fluorescent tube bulb?

Reply 987

A*da*m

Original post by the_german_boy

Phi mesons contain a strange-antistrange pair

The total strangeness is therefore (-1) + (+1) = 0

That still means that this particular meson contains strange quarks, which I think was the initial problem

Reply 988

a.a.k

Original post by tanyapotter

how likely do you think it is that we'll get asked a question on the starter unit of a fluorescent tube bulb?

There deffinitly will be queation on it. But not sure what u mean by starter unit

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Reply 989

particlestudent

Can we please get 8 marks on Oscilloscopes, like the question in January 2011 :biggrin:

. 4 marks for drawing an oscilloscope wave :biggrin:

Reply 990

wallpaperpaste

Can anyone direct me to or give me some advice on past electricity and circuit 6 mark questions thanks

Reply 991

tanyapotter

guys, i'm really confused about one thing in particular. do K mesons interact via the strong force at all? they're hadrons so they should do, right? but it's only when they interact via weak that we know strangeness is not conserved..right?

furthermore, all hadrons (except the proton) decay via the weak interaction, correct?

Reply 992

a.a.k

Try Jan12 paper if anyone wants to practise GOOD

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Reply 993

xMillnsy

(Q4a June 12) explain why the emitted electrons have a range of frequencies up to a maximum value?

Reply 994

the_german_boy

Original post by the_googly

Can somebody give me a six mark answer in bullet points for this question. Thanks

Posted from TSR Mobile

Connect a diode to a dc power supply, and in series with an ammeter and variable resistor. connect a voltmeter in parallel with the diode.

each bullet point is worth a mark:

-connect the circuit as shown in the diagram, with the diode forward biased
-adjust the variable resistor such that the current in the circuit is at a minimum. take a reading of the current (I) and the pd (V).
-gradually increase the current, repeating these readings at regular intervals, up to a maximum point
-now switch the cables connected to the dc power supply, such that the diode is now reverse biased
-replace the ammeter with a milliammeter, and repeat the readings for I and V, gradually increasing I
-plot a graph of I/V

Reply 995

a.a.k

Original post by tanyapotter

Hint its a Hadron

Posted from TSR Mobile

Reply 996

tanyapotter

Original post by a.a.k

There deffinitly will be queation on it. But not sure what u mean by starter unit

Posted from TSR Mobile

basically, mains voltage is too low to heat the mercury vapour in the fluorescent tube directly, so a starter unit is used. when the tube is switched on, a current flows through the argon gas in the unit, heating the bimetallic strip and causing it to bend, closing the switch. at this point, the electrodes are hot enough to heat the vapour. when the bimetallic strip closes, the current through the argon stops so the switch opens and the current is now flowing between the filament and the positive electrode.

it was a vague section in the text book but i didn't want to take any chances and basically learnt the whole thing, when i really could have been doing something a bit more productive.

Reply 997

the_german_boy

Original post by A*da*m

That still means that this particular meson contains strange quarks, which I think was the initial problem

Could you link me the original question? :smile:

Reply 998

A*da*m

Original post by xMillnsy

(Q4a June 12) explain why the emitted electrons have a range of frequencies up to a maximum value?

All the photons have a fixed energy equal to hf. The photon energy minus the work function energy is equal to the maximum kinetic energy. This is because the work function is the minimum energy required to remove an electron from the SURFACE of a metal. Therefore electrons lower down in the metal need more energy than the work function energy to leave the electron, so there is less kinetic energy left for these electrons once they have been given enough energy to leave the metal, so a range of kinetic energies are observed :smile:

Reply 999

abc900

Could anyone provide useful resources on understanding oscilloscopes or explain it for me please? I really don't understand them and i'm terrified in case there's lots of marks on them.