Paradoxica
-insert title here-
personally, 16 (a) is the harder question for me, because i understand irrationality proofs like physicists understand newtonian mechanics
BoS trials Maths and Chemistry 2020 (1 Viewer)
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Imagine having to prove irrationality when you can just plug it into a calculator. QED.
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I reckon Q16a) is probably as challenging as you can get when it comes to resisted projectile motion, mainly because a sneaky trick is needed to get part (ii) out, otherwise you're going to be stuck. Most textbook or past exam questions (of which there are very few) are far more straightforward.
Paradoxica
-insert title here-
numbers have an end
therefore all decimal expansions terminate
therefore all real numbers are rational
this is satire btw
is there even gonna be a nesa party with covid
check their solutions
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The direction in which you resolve the forces is not horizontal/vertical. It is parallel/perpendicular to the inclined surface. This is because the net force of the object is parallel to the inclined surface.
Ohh I get it now, thank you
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Not yet. Maths is taking priority at this stage as their exams are sooner. Chemistry should be out around a week after.
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Just marked Q12 of Maths Ext1 and have some feedback on Q12e)i)
The question asked students to prove a given vector relationship between A, B and P given that
A very common response from students was to assert that
\overrightarrow{BP})
This is not correct because the given ratio above is purely related to vector magnitudes. To convert to vector equations, you need to take into consideration both the magnitude AND the direction of the vectors. Notice that vector AP does NOT point into the same direction as BP (as P lies in the interval AB) so they cannot be related by a positive scalar. Many students attempted to fudge the result when they realised the algebra did not work out from this assertion. Better responses carefully considered the directions that the vectors were pointing and often related the directions of AP and AB.
The question asked students to prove a given vector relationship between A, B and P given that
A very common response from students was to assert that
This is not correct because the given ratio above is purely related to vector magnitudes. To convert to vector equations, you need to take into consideration both the magnitude AND the direction of the vectors. Notice that vector AP does NOT point into the same direction as BP (as P lies in the interval AB) so they cannot be related by a positive scalar. Many students attempted to fudge the result when they realised the algebra did not work out from this assertion. Better responses carefully considered the directions that the vectors were pointing and often related the directions of AP and AB.
ok thanks
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Aiming for tomorrow. In the meantime, feel free to ask any specific questions here if you want some answers.