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AQA Physics PHYA1 - 24 May 2016 - RESIT [Exam Discussion Thread]

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Reply 180

Shta15

Is stangeness not also conserved with a neutral pion

Reply 181

clarkey500

Original post by CourtlyCanter

What do you mean?
K^1 (strangeness +1) ==> pi^1 (strangeness +0) + X (strangeness MUST be +1)

The only particle with a strangeness of +1 and charge of 0 is K^0 so shouldn't X be K^0 ?

The equation for K+ decay is:
K^+ ---> pi^+ +pi^0

There are many decays that happen to a K^+ (according to Wiki) but only one that forms a pi^+ and only one other product the pi^0

However, K^0 may be possible but I just put what I knew from the textbook!

Reply 182

Mustang Wanted

Original post by Shta15

What did you tick when classifying particles.
I ticked hadron and meson for the kaon
And the others were a lepton

I did the same
No ticks for Baryon column

Reply 183

Lazarus26

Original post by Goldfly

Sounds right to me. What about the next power one?

Which one? I cant really remember the paper

Reply 184

emsieMC

Overall how does everyone think the grade boundaries are going to be on this one?

Reply 185

clarkey500

Original post by Lazarus26

I got 4400W
:/

Me as well! :smile:

Reply 186

Einstein1997

It's Pi0.

I also got 4400 and 34.something

3.6 for the very last question

(edited 7 years ago)

Reply 187

Mustang Wanted

Original post by emsieMC

Overall how does everyone think the grade boundaries are going to be on this one?

Hard to say really. I'd say about 55 for A +/-5

Reply 188

emsieMC

Think they will be low or high? I think because of the electricity questions they will be a bit low

Reply 189

CourtlyCanter

Original post by Goldfly

What were the two reasons to have a low resistance? I got that one was to provide a high enough current for the oven to function but I was unsure about the other one.

I think I put-
1. Total resistance in the circuit is smaller, meaning the current is bigger as V(EMF) is constant. V=IR, when I is greater, the V across the heating element is also greater.

2.Since V=IR, Heating element in oven shares a larger proportion of voltage as its R occupies a larger proportion of the total resistance in the circuit. Since P=VI the power generated across heating element should also be greater.

What do you guys think of these answers? Are they okay?

(edited 7 years ago)

Reply 190

thxmas7

It is a pio as strangeness isnt conserved in decay (weak interaction)

Reply 191

clarkey500

Original post by Einstein1997

It's Pi0.

I also got 4400 and 34.something

I got 4400 and 34 I rounded to 34 (as everything we were given in the question was 2sf) so we're probably both right! (Yay marks!!)

Reply 192

Mustang Wanted

Original post by emsieMC

Think they will be low or high? I think because of the electricity questions they will be a bit low

Maybe you're right. They might allow it to us this year as this is the last exam of the same specification :smile:

Reply 193

RUNSran

which question did yo guys get 4400 and how? I got 8800 on the first power question

Reply 194

Jonah1958

For the rms voltage over the heating element i ended getting 229.5V as 0.5v lost to resistance of wires, got a current of about 19A.

Pretty sure i messed up somewhere :frown:

Reply 195

RUNSran

Original post by Jonah1958

For the rms voltage over the heating element i ended getting 229.5V as 0.5v lost to resistance of wires, got a current of about 19A.

Pretty sure i messed up somewhere :frown:

i got the same ! im sure we are right

Reply 196

Mustang Wanted

Original post by Jonah1958

For the rms voltage over the heating element i ended getting 229.5V as 0.5v lost to resistance of wires, got a current of about 19A.

Pretty sure i messed up somewhere :frown:

Got the same current. Don't remember the voltage though