BoS trials Maths and Chemistry 2020 (1 Viewer)

Trebla

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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.
 

terryz

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All jokes aside it is not me, but someone I know. He does not want people to know as he is a humble man. Keep working hard and maybe you can see him at NESA Party!
 

ultra908

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All jokes aside it is not me, but someone I know. He does not want people to know as he is a humble man. Keep working hard and maybe you can see him at NESA Party!
is there even gonna be a nesa party with covid
 

sysysysy

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Hi, can someone explain to me why it's N=mg cos theta and not mg=N cos theta for Q14a(i)? and also why is it suddenly sin theta for a(ii)?

This is for extension 2 paper btw, thanks!
 

YonOra

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When can we expect the Ext 1 answers?
 

beetree1

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Hi, can someone explain to me why it's N=mg cos theta and not mg=N cos theta for Q14a(i)? and also why is it suddenly sin theta for a(ii)?

This is for extension 2 paper btw, thanks!
check their solutions
 

Trebla

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Hi, can someone explain to me why it's N=mg cos theta and not mg=N cos theta for Q14a(i)? and also why is it suddenly sin theta for a(ii)?

This is for extension 2 paper btw, thanks!
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.
 

sysysysy

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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 :)
 

Trebla

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Are the solutions to the BOS chem 2020 trial out yet?
Not yet. Maths is taking priority at this stage as their exams are sooner. Chemistry should be out around a week after.
 

Trebla

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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



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.
 

OnJob

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Does anyone know when EXT 1 answers will be released?
 

Trebla

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Does anyone know when EXT 1 answers will be released?
Aiming for tomorrow. In the meantime, feel free to ask any specific questions here if you want some answers.
 

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