petayani
New Member
My lack of organisation has left me with very little knowledge (or at least practise) of mechanics. Does anyone have some tips to help poor cramming little me?
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Mechanics advice please (1 Viewer)
- Thread starter petayani
- Start date
S
Shuter
Guest
Yes, give up.
petayani
New Member
hmmmm... how much basic physics understanding? You see, I don't do physics. I guess that's the end of me, huh?
theVirus
New Member
Mechanics
Man, you can't be as fucked as me... Or atleast you would like to hope not. I am planning on getting 55% in the HSC examination for Extension 2. Get out your text book: Turn to mechanics, and start studying. If you have already done it, get the Excel Textbook - it is a good summary - and try to do the examples without looking at the answers. Just use them as a guide if you need them. After you have done all of the example questions in that, you are fucked because you waited until the weekend! Otherwise, you should have access to a big book of past papers that goes from like 1980 or something. Get that book out and do MORE questions. You have two days and tonight left, that makes for 15 hours of studying, atleast! In that time you should be able to easily cover the Mechanics topic even if you hadn't learnt it before.
Man, you can't be as fucked as me... Or atleast you would like to hope not. I am planning on getting 55% in the HSC examination for Extension 2. Get out your text book: Turn to mechanics, and start studying. If you have already done it, get the Excel Textbook - it is a good summary - and try to do the examples without looking at the answers. Just use them as a guide if you need them. After you have done all of the example questions in that, you are fucked because you waited until the weekend! Otherwise, you should have access to a big book of past papers that goes from like 1980 or something. Get that book out and do MORE questions. You have two days and tonight left, that makes for 15 hours of studying, atleast! In that time you should be able to easily cover the Mechanics topic even if you hadn't learnt it before.
petayani
New Member
Thanks theVirus. I'm glad you think it's possible. neway, guess I'd better go do what you said now and stop getting stuck on these fandangled forum things 
Rorix
Active Member
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- HSC
- 2005
MY QUICK GUIDE TO MECHANICS
1) EVERY QUESTION BASICALLY INVOLVES THE SOLVING OF TWO EQUATIONS
a) the vertical forces
b) the horizontal forces
Note that many forces aren't either horizontal or vertical. For these, we need to use our good friend TRIG.
If you get stuck, just draw a triangle. This is basic year 9 shit here people.
Now you have those equations, you're SET. Generally, the questions will require you to derive (no, nothing to do with calculus, please pay attention) some sort of relationship between forces from the vertical forces equation (this is the less complex one, nothing to do with imaginary numbers) and then use that to find a value of omega in the horizontal forces equation. omega is that thing that you think is a w.
Now, SOME QUESTIONS ARE DECEPTIVELY EASY. You go through the above steps and you say, Rorix, what the fuck? I didn't even need to use the vertical forces equation. Well, good on ya champ. For future reference, generally when they give you numbers, like r=20, you might not need to use both. Just use your brain, I'm not doing the test for you.
Now, THE LAST TRICK. SOMETIMES, JUST SOMETIMES, they'll tell you that the string length is l so your mrw^2 doesn't have an l. THIS IS REAL EASY TO FIX. LOOK AT YOUR DIAGRAM (did I mention a diagram was important? Draw a fucking diagram) and use your good friends SIN or COS (usually sin, unless you're using some nonorthodox angle).
LASTLY, WRITE SOME FUCKING UNITS DOWN. DO YOU WANT TO THROW MARKS OUT THE WINDOW OR DO YOU JUST NOT CARE?
1) EVERY QUESTION BASICALLY INVOLVES THE SOLVING OF TWO EQUATIONS
a) the vertical forces
b) the horizontal forces
Note that many forces aren't either horizontal or vertical. For these, we need to use our good friend TRIG.
If you get stuck, just draw a triangle. This is basic year 9 shit here people.
Now you have those equations, you're SET. Generally, the questions will require you to derive (no, nothing to do with calculus, please pay attention) some sort of relationship between forces from the vertical forces equation (this is the less complex one, nothing to do with imaginary numbers) and then use that to find a value of omega in the horizontal forces equation. omega is that thing that you think is a w.
Now, SOME QUESTIONS ARE DECEPTIVELY EASY. You go through the above steps and you say, Rorix, what the fuck? I didn't even need to use the vertical forces equation. Well, good on ya champ. For future reference, generally when they give you numbers, like r=20, you might not need to use both. Just use your brain, I'm not doing the test for you.
Now, THE LAST TRICK. SOMETIMES, JUST SOMETIMES, they'll tell you that the string length is l so your mrw^2 doesn't have an l. THIS IS REAL EASY TO FIX. LOOK AT YOUR DIAGRAM (did I mention a diagram was important? Draw a fucking diagram) and use your good friends SIN or COS (usually sin, unless you're using some nonorthodox angle).
LASTLY, WRITE SOME FUCKING UNITS DOWN. DO YOU WANT TO THROW MARKS OUT THE WINDOW OR DO YOU JUST NOT CARE?
ok
A class of 22 students is to be divided into four groups consisting of 4, 5, 6 and
7 students.
(i) In how many ways can this be done? Leave your answer in unsimplified
form.
(ii) Suppose that the four groups have been chosen. In how many ways can the 22 students be arranged around a circular table if the students in each group are to be seated together? Leave your answer in unsimplified form.
A class of 22 students is to be divided into four groups consisting of 4, 5, 6 and
7 students.
(i) In how many ways can this be done? Leave your answer in unsimplified
form.
(ii) Suppose that the four groups have been chosen. In how many ways can the 22 students be arranged around a circular table if the students in each group are to be seated together? Leave your answer in unsimplified form.