Advice for study on Conics and Mechanics (1 Viewer)

[MC Squidge]

Ok so i did well in the first 5 chapters (complex, curve sketching, polynomials, volumes and integration), took a while but i got a decent understanding of them. I am struggling with mechanics and conics though. can someone give me advice how to study for them? i have every ext 2 textbook and alot of past papers. terry lee was no help AT ALL for mechanics so dont suggest that

 

[Dumbledore]

conics: just have to do heaps of questions on it whether textbook or past paper

mechanics(resisted): make sure u get ur first equation right usually F=ma=f(x) or F=ma=f(t), then just use ur basic 3u kinematic laws like a = vdv/dx for first case or a = dv/dt for second case, and continue manipulating till you get the answer

mechanics(circular): for those pendulum questions that appear so often in past papers, draw a diagram, always split the forces into their individual perpendicular components, usually u'll get 4 equations and use these simultaneously to get the answer. also don't forget that when the mass is touching an object, by newtons 3rd law you have to draw a normal reaction force on ur diagram.

its rarer to see the UCM questions in papers but they're useful for understanding the concepts of circular motion if thats the part ur struggling with

 

[MC Squidge]

thanks for the mechanics advice. any specific text books that do these chapters well?

 

[untouchablecuz]

i used cambridge and thought it was pretty good. but as always said, theres no substitute for past papers, especially older CSSA type questions (usually several topics appear in one question e.g. conics + mechanics).

with mechanics, alot of it is generally the same.

for resisted motion, make sure you know how to manipulate fractions such that you dont need to do long division (e.g. x/(1+kx) = xk/k(1+kx) = (1+kx-1)/k(1+ kx) = 1 - 1/k(1+kx)).

for circular motion, be aware of normal forces (perpendicular to the surface at the point of contact(s)), make sure that your extremely proficient in resolving forces, whether your solving them parallell to the horizontal at a slight angle (and so on) > thats basically all that circular motion is. also, remember that that the centripetal force is the RESULTANT force, that is, it is caused by the several force components acting on the particle -> its not a force in itself that is purposely applied (if you understand what i mean)

for conics, practice practice practice AND use similar triangles wherever you can AND use the focus-directrix definition whenever you encounter a focus, if needed (i.e. PS/PM = e) -> it can at times save on alot of algebra.