*** Leaving Cert PHYSICS 2014 ***

aleatorio

Beautiful paper confident for the A1 I think :pac:
Did every question except for Q6 because ew mechanics.. XD

qweerty

Daniel2590 wrote: »

Joules law, conservation of momentum, speed of sound in air and snells law were the experiments. Q6 had derivation of F=ma, difference between vectors and scalars, then the calculation was based on a golf ball being hit (find initial speed and Max height)

Thanks for a thorougly comprehensive reply, man.

omara95

Nice enough paper. Happy with it.

deadpixel

Lovely paper, couldn't have asked for much better in terms of what came up!

aleatorio

Ok so I scribbled down a majority of my calculations answers:

Q2: n=1.175
Q3: v= 339
Q4: Temp = 25.5
Q5: (b) 6.563 x 10^23 (d) 75.6J (h) 2.1627 x 10^-19
Q7: Energy of photon = 2.8036 x 10^-19 Number of lines = 400
Q8: 7.628 x 10^24 nuclei
Q9: Charge = 3.6 x 10^-5C Energy = 2.16 x 10^-4 New capacitance: 4 x 10^-6F
Q10: speed = 29.025 Resistance = 17.36 ohms
Q11: Frequency = 2.4177 x 10^14Hz Decay constant = 5.77622 x 10^-4
Q12:
(A) Length = 4.13cm Period = 0.2565s
(C) Mass = 0.014375kg Temp = 21.45 (these are wrong, just realized I only did it for 1 ice cube )

Daniel2590

Did anyone who does applied maths use projectiles for Q6 actually? I used max height when Vy = 0 and all that craic :pac:

LifeasaPigeon

Daniel2590 wrote: »

Did anyone who does applied maths use projectiles for Q6 actually? I used max height when Vy = 0 and all that craic :pac:

Yeah, and I usually avoid mechanics but it was too lovely not to do applied maths finally came in handy for something!

qweerty

Daniel2590 wrote: »

Did anyone who does applied maths use projectiles for Q6 actually? I used max height when Vy = 0 and all that craic :pac:

Lol. I'd say the corrector will think you're such a prat. They'll be dying to deduct marks!

qweerty

LifeasaPigeon wrote: »

Yeah, and I usually avoid mechanics but it was too lovely not to do applied maths finally came in handy for something!

Why do you avoid Mechanics considering you do AM?

LifeasaPigeon

qweerty wrote: »

Why do you avoid Mechanics considering you do AM?

I'm really bad at it doesn't look like I'll be counting it for points

AtomicKoala

Ah, so we were the year who finally got a comprehension question on the option.

We're one of a kind! :pac:

b0gg3r

Such a paper. Delighted. Only thing I know now that I got wrong was the last part of question 11, the formula about the momentum of a particle in a cyclotron.

Hoping the marking scheme isn't too rough, but most of the guys in my school found it easy enough, one nutter even did every question!

aleatorio

b0gg3r wrote: »

Such a paper. Delighted. Only thing I know now that I got wrong was the last part of question 11, the formula about the momentum of a particle in a cyclotron.

Hoping the marking scheme isn't too rough, but most of the guys in my school found it easy enough, one nutter even did every question!

Was that mv = qBr ?

AtomicKoala

aleatorio wrote: »

Was that mv = qBr ?

Yeah, I assume you should write p = qBr, as p is momentum (p = mv)

aleatorio

AtomicKoala wrote: »

Yeah, I assume you should write p = qBr, as p is momentum (p = mv)

Oh.. Oops XD doubt I'd lose much for that though :P

Daithi MacG

Daniel2590 wrote: »

Did anyone who does applied maths use projectiles for Q6 actually? I used max height when Vy = 0 and all that craic :pac:

My friend did it that way and said he got something like 53m, whereas I got something around 13m. What did you get?

LifeasaPigeon

Daithi MacG wrote: »

My friend did it that way and said he got something like 53m, whereas I got something around 13m. What did you get?

I think I got around 13m too

FatRat

What a test! So unbelievably easy. Suspiciously too easy tbh... Something's up with how easy it was.

AtomicKoala

FatRat wrote: »

What a test! So unbelievably easy. Suspiciously too easy tbh... Something's up with how easy it was.

Maybe you did OL by accident? :pac:

Daithi MacG

FatRat wrote: »

What a test! So unbelievably easy. Suspiciously too easy tbh... Something's up with how easy it was.

I'd say it'll be marked hard, lots of detail needed probably.

CL987

aleatorio wrote: »

Ok so I scribbled down a majority of my calculations answers:

Q2: n=1.175
Q3: v= 339
Q4: Temp = 25.5
Q5: (b) 6.563 x 10^23 (d) 75.6J (h) 2.1627 x 10^-19
Q7: Energy of photon = 2.8036 x 10^-19 Number of lines = 400
Q8: 7.628 x 10^24 nuclei
Q9: Charge = 3.6 x 10^-5C Energy = 2.16 x 10^-4 New capacitance: 4 x 10^-6F
Q10: speed = 29.025 Resistance = 17.36 ohms
Q11: Frequency = 2.4177 x 10^14Hz Decay constant = 5.77622 x 10^-4
Q12:
(A) Length = 4.13cm Period = 0.2565s
(C) Mass = 0.014375kg Temp = 21.45 (these are wrong, just realized I only did it for 1 ice cube )

got the exact same for every q, including the wrong ice calculation haha

aleatorio

CL987 wrote: »

got the exact same for every q, including the wrong ice calculation haha

Hahahah well hopefully we got everything right then except for that stupid ice q! :pac:

Ompala

Daniel2590 wrote: »

Joules law, conservation of momentum, speed of sound in air and snells law were the experiments. Q6 had derivation of F=ma, difference between vectors and scalars, then the calculation was based on a golf ball being hit (find initial speed and Max height)

Finally! Hoped that would appear 2 years ago when I did the Leaving and last year when I was giving grinds in physics!

Sounds like a straightforward paper from what ye are saying, if you had done the work you would have no problems with it, but then again that is always the way with LC Physics.

FatRat

The diffraction grating formula was called by someone here yesterday.. I had said if light wasn't in section then q7 would be the diffraction grating experiment! Seems to be a trend putting an experiment type q in q7.

Can somebody write out the equation for the nuclear reaction in q8,just to be sure.

Daithi MacG

aleatorio wrote: »

Ok so I scribbled down a majority of my calculations answers:

Q2: n=1.175
Q3: v= 339
Q4: Temp = 25.5
Q5: (b) 6.563 x 10^23 (d) 75.6J (h) 2.1627 x 10^-19
Q7: Energy of photon = 2.8036 x 10^-19 Number of lines = 400
Q8: 7.628 x 10^24 nuclei
Q9: Charge = 3.6 x 10^-5C Energy = 2.16 x 10^-4 New capacitance: 4 x 10^-6F
Q10: speed = 29.025 Resistance = 17.36 ohms
Q11: Frequency = 2.4177 x 10^14Hz Decay constant = 5.77622 x 10^-4
Q12:
(A) Length = 4.13cm Period = 0.2565s
(C) Mass = 0.014375kg Temp = 21.45 (these are wrong, just realized I only did it for 1 ice cube )

Think I got n=1.475 for Q.2...whoops
I remembered to multiply by three for three ice cubes and got an answer of around 16 degrees for the temp.

aleatorio

Daithi MacG wrote: »

Think I got n=1.475 for Q.2...whoops
I remembered to multiply by three for three ice cubes and got an answer of around 16 degrees for the temp.

I could be wrong idk :pac:

Did you remember to take it away from the initial temp? It asked for the temp of the water not the change in temp


Does anyone know if I got the wrong mass for the icecubes how will that impact the marking for the rest of the q?

2thousand14

Daithi MacG wrote: »

Think I got n=1.475 for Q.2...whoops
I remembered to multiply by three for three ice cubes and got an answer of around 16 degrees for the temp.

I got 1.475 too

XtotheZ

2thousand14 wrote: »

I got 1.475 too

yup 1.48.


didnt really like that paper tbh

Daithi MacG

aleatorio wrote: »

I could be wrong idk :pac:

Did you remember to take it away from the initial temp? It asked for the temp of the water not the change in temp


Does anyone know if I got the wrong mass for the icecubes how will that impact the marking for the rest of the q?

Q.2 was the refractive index I thought? That's Q.4 you're thinking of, is it? For that I added the initial temperature, because my graph was I^2 against change in temp.

Nicke011

Lovely paper, it went unexpectedly good
Hoping for a A2/B1/B2

The marking scheme is probably going to be very rough

Q2 1.47
Q4 26
Q5 U-value, go construction studies!
Q6 Net force = 0, golfer is not moving;
Max height 12. something (about 13 as far as I remember); Let's go applied maths!
Q8 Engineering all the way!
238/92U + 1/0n = 239/95Pu + 2*(0/-1e)
Q12
b) V=-4.28cm
c) T=15.68 degrees