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**Physics...Before/After**

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12357…16

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    #122
    Wanchor
    Registered Users Posts: 114 ✭✭Wanchor


    BL1993 wrote: »
    Yes.

    Did the question specifically ask for an integer/float/surd?


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    #123
    RedTexan
    Registered Users Posts: 217 ✭✭RedTexan


    Wanchor wrote: »
    Did the question specifically ask for an integer/float/surd?
    Nope, I give it as 5.828 or whatever


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    #124
    BL1993
    Closed Accounts Posts: 341 ✭✭BL1993


    RedTexan wrote: »
    Yera, I wouldn't be too worried, figures this year people 1 will be the one that will be defining. The former vice principal of my school is the assistant chief examiner and he said that if you wrote anything at all down for any question the likelihood is that you will get 5 marks upwards! And sure hey, there's bigger fish to fry next Monday!
    Well, hopefully they'll give it to me. I've worked so hard for that bloody A1 that it would kill me a little inside if I didn't get it. :'(


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    #125
    Wanchor
    Registered Users Posts: 114 ✭✭Wanchor


    RedTexan wrote: »
    Nope, I give it as 5.828 or whatever

    I left it as k = x.


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    #126
    FinnD
    Registered Users Posts: 125 ✭✭FinnD


    Should I be okay if I left out current electricity and electromagnetism? I tend to stay away from Q5 aswell


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    #127
    BlueTexan
    Registered Users Posts: 3 ✭BlueTexan


    RedTexan wrote: »
    Yera, I wouldn't be too worried, figures this year people 1 will be the one that will be defining. The former vice principal of my school is the assistant chief examiner and he said that if you wrote anything at all down for any question the likelihood is that you will get 5 marks upwards! And sure hey, there's bigger fish to fry next Monday!

    Good man ya.


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    #128
    Liveforrugby
    Registered Users Posts: 343 ✭✭Liveforrugby


    FinnD wrote: »
    Should I be okay if I left out current electricity and electromagnetism? I tend to stay away from Q5 aswell

    Yea you should be alright, concentrate on the topics you know well. Besides it's too late to start learning new stuff now


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    #129
    Dwellingdweller
    Closed Accounts Posts: 825 ✭✭✭Dwellingdweller


    Does anyone know if a question has come up on Static Electricity in the LC recently where you would have had to use the F=Q/4*π*ε*d^2 formula instead of E=F/Q?


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    #130
    Incompetent
    Registered Users Posts: 442 ✭✭Incompetent


    Lads anyone know for the pendulum which goes on which axis?

    One book says T^2 goes on x, one says on y


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    #131
    Darksider
    Registered Users Posts: 111 ✭✭Darksider


    Incompetent wrote: »
    Lads anyone know for the pendulum which goes on which axis?

    One book says T^2 goes on x, one says on y

    Since its direct proportionality, either way would work. You would still get a straight line through the origin. The way I like to do it is have the controlled variable (ie the one we manually adjust) on the x axis and the response variable (the one that changes as we change x) on the y axis.

    Just remember, slope = y/x. Just know that in case you need to use slope for any calculations.


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    #132
    RedTexan
    Registered Users Posts: 217 ✭✭RedTexan


    Incompetent wrote: »
    Lads anyone know for the pendulum which goes on which axis?

    One book says T^2 goes on x, one says on y
    It really doesn't matter as long as you know the slope is equal to 2pi/g for T^2 on the y axis and that inverted for it on the x axis


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    #133
    Dwellingdweller
    Closed Accounts Posts: 825 ✭✭✭Dwellingdweller


    Incompetent wrote: »
    Lads anyone know for the pendulum which goes on which axis?

    One book says T^2 goes on x, one says on y

    Just had a quick look at that myself. It's l on the y axis and T^2 on the x axis, but it's not obvious at first, so I'll type out how I got to grips with it, hopefully it'll help ya understand it too. Those graphs can be confusing.

    So you start with your formula:
    T=(2pi)*(sqrt(l/g))
    Square both sides
    T^2=4(pi^2)*(l/g)
    So now you have an equation in the form y=mx+c. c=0 because the graph goes through the origin, so the equation is just y=mx. You need to switch it around to get g.
    g=4(pi^2)*(l/t^2)
    As you can see l/t^2 is the slope, just multiply 4(pi^2)(slope) to get g. :) Hope that helped!


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    #134
    Incompetent
    Registered Users Posts: 442 ✭✭Incompetent


    Cheers lads! I get it now :)


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    #135
    fizzyorange
    Closed Accounts Posts: 592 ✭✭✭fizzyorange


    Hey lads, no chance there are any experiments in physics that are strictly HL?


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    #136
    Wanchor
    Registered Users Posts: 114 ✭✭Wanchor


    This made me chuckle while revising:

    yDtFv.jpg


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    #137
    ei.sderob
    Closed Accounts Posts: 108 ✭✭ei.sderob


    I've left out aaaaalllll of electricity and capacitance. Basically anything of an electrical nature. As long as the short qs don't have like 3 or 4 electrical questions I should be grand. Hopefully we'll get a nice mechanics question:D


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    #138
    Nitsuj
    Registered Users Posts: 176 ✭✭Nitsuj


    fizzyorange wrote: »
    Hey lads, no chance there are any experiments in physics that are strictly HL?
    would really like to know this as well.


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    #139
    cocopopsxx
    Registered Users Posts: 261 ✭✭cocopopsxx


    I'm contemplating not sitting the physics exam AT ALL. I'm so not prepared and I don't get physics at all at all- got a D last year!! I'm seriously panicking and it'll effect accounting (my fav subject) as well, it did last year. :( bad idea? And my parents will flip!


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    #140
    Wesc.
    Registered Users Posts: 715 ✭✭✭Wesc.


    cocopopsxx wrote: »
    I'm contemplating not sitting the physics exam AT ALL. I'm so not prepared and I don't get physics at all at all- got a D last year!! I'm seriously panicking and it'll effect accounting (my fav subject) as well, it did last year. :( bad idea? And my parents will flip!

    Just sit it, who knows the paper might suit you! Imagine how pissed you'd be if you looked at the paper realising that you could of done well?
    Besides, you can always leave a bit early.


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    #141
    cocopopsxx
    Registered Users Posts: 261 ✭✭cocopopsxx


    Wesc. wrote: »
    cocopopsxx wrote: »
    I'm contemplating not sitting the physics exam AT ALL. I'm so not prepared and I don't get physics at all at all- got a D last year!! I'm seriously panicking and it'll effect accounting (my fav subject) as well, it did last year. :( bad idea? And my parents will flip!

    Just sit it, who knows the paper might suit you! Imagine how pissed you'd be if you looked at the paper realising that you could of done well?
    Besides, you can always leave a bit early.

    True, but I act don't know anything except sound,light and heat. And may be a bit of mechanics. And I don't want a D on my report :/


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    #142
    RedTexan
    Registered Users Posts: 217 ✭✭RedTexan


    cocopopsxx wrote: »
    True, but I act don't know anything except sound,light and heat. And may be a bit of mechanics. And I don't want a D on my report :/
    Probably better than a NG?


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    #143
    mathstalk
    Registered Users Posts: 162 ✭✭mathstalk


    It just struck me that pretty much every famous scientist has an equation named after them, so if a question comes up like, "What contribution did so-and-so make to physics?" and I haven't a clue… "Well, er, he developed the 'so-and-so' equation." Worth a shot?
    cocopopsxx wrote: »
    I'm contemplating not sitting the physics exam AT ALL. I'm so not prepared and I don't get physics at all at all- got a D last year!! I'm seriously panicking and it'll effect accounting (my fav subject) as well, it did last year. frown.gif bad idea? And my parents will flip!

    You'll be grand. The equations are in the tables so just pick them up from the tables and write them down on the paper. That's 3 out of 9 marks already. If you're not sure what equation to use then write 5 or 6 on your paper. Then just sub in numbers for letters and hope for the best. As for the definitions, once again, a lot are actually in the tables, i.e. Coulomb's law, the law of gravitation. If your doing honours then ask for the pass paper, that is, if you're not comfortable on the day. Don't worry if you failed the mocks (so did I), the leaving cert paper tends to be easier. A lot of the paper is applications of physics, "State 2 applications of convex lenses"; these are quite guessable. Even if yo do fail, you're not loosing anything compared to not sitting the paper at all. Just go in and do it. Presumably you have 6 other subject so Physics won't even count. Where's the pressure?


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    #144
    cocopopsxx
    Registered Users Posts: 261 ✭✭cocopopsxx


    Okay, thank you guys. I think I just panicked! So if I know my experiments well, then waves,sound,light,mechanics,heat and modern physics- will I have a Chance of getting at least a C? :/


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    #145
    cocopopsxx
    Registered Users Posts: 261 ✭✭cocopopsxx


    ei.sderob wrote: »
    I've left out aaaaalllll of electricity and capacitance. Basically anything of an electrical nature. As long as the short qs don't have like 3 or 4 electrical questions I should be grand. Hopefully we'll get a nice mechanics question:D

    Oh I'm not the only one!! Do you think that's safe and they won't be nasty and throw electricity questions everywhere this year? Will I get at least a C if I leave out electricity totally?


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    #146
    ei.sderob
    Closed Accounts Posts: 108 ✭✭ei.sderob


    cocopopsxx wrote: »
    Oh I'm not the only one!! Do you think that's safe and they won't be nasty and throw electricity questions everywhere this year? Will I get at least a C if I leave out electricity totally?

    Haha, leaving out electricity is no big deal man. A LOT of people do it. I'm leaving it all out and still going for an A1 like. Doing App math too though so it's kind of an advantage with question . All I hope is that we get 2 max in the short qs and that question 11 is on something other electricity. Nuclear hopefully:D


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    #147
    Nitsuj
    Registered Users Posts: 176 ✭✭Nitsuj


    If you look at the papers, there are years where you could get away without doing electricity AND mechanics. Leaving out just one of them will be grand. I'm in the same boat as you, cocopopsxx, so I've decided to do OL. **** it, I just want to get these exams over with at this stage.


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    #148
    fizzyorange
    Closed Accounts Posts: 592 ✭✭✭fizzyorange


    Nitsuj wrote: »
    would really like to know this as well.

    Just figured out the experiments we don't need at OL. :)

    Mechanics
    -Investigation of the relationship between period and length for a simple pendulum and hence calculation of g

    Light, Sound and Waves
    -Only need one experiment of finding the refractive index of something, so I'm choosing to leave out Finding the refractive index of water
    -Investigation of the variation of the fundamental frequency of a stretched string with tension

    Heat
    -Only need one experiment of measuring specific heat capacity, so I'm leaving out Measurement of the SHC of a metal by electrical method

    And all of the electricity experiments are OL as well, but I don't plan on covering any electricity experiments. :P


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    #149
    insua
    Registered Users Posts: 30 ✭insua


    If u just prepare the experiments, mechanics, definitions (Q5) and particle physics u can do surprisingly well


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    #150
    Bears and Vodka
    Registered Users Posts: 2,249 ✭✭✭Bears and Vodka


    Nitsuj wrote: »
    If you look at the papers, there are years where you could get away without doing electricity AND mechanics.

    Kind of relying on this now :/ to make things worse I'm kinda bad at optics and not the best at sound. Plenty of work to do tomorrow.


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    #151
    ganon
    Registered Users Posts: 52 ✭✭ganon


    I hate electricity too but it's the experiments i don't get, Joule's law is the only elec. experiment i'm learning, it has a fair chance of coming up and if not i'll just do the other 3


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