MedVision ad

BoS trials Maths and Chemistry 2020 (3 Viewers)

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,391
Gender
Male
HSC
2006
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

New Member
Joined
Jan 2, 2020
Messages
2
Gender
Male
HSC
2020
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

Active Member
Joined
May 11, 2019
Messages
151
Gender
Male
HSC
2020
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

New Member
Joined
Oct 13, 2020
Messages
2
Gender
Female
HSC
2020
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

Well-Known Member
Joined
Apr 21, 2020
Messages
375
Gender
Undisclosed
HSC
2021
When can we expect the Ext 1 answers?
 

beetree1

Well-Known Member
Joined
Feb 10, 2019
Messages
539
Gender
Female
HSC
2020
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

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,391
Gender
Male
HSC
2006
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

New Member
Joined
Oct 13, 2020
Messages
2
Gender
Female
HSC
2020
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

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,391
Gender
Male
HSC
2006
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

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,391
Gender
Male
HSC
2006
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

New Member
Joined
Jun 18, 2020
Messages
16
Gender
Male
HSC
2020
Does anyone know when EXT 1 answers will be released?
 

Trebla

Administrator
Administrator
Joined
Feb 16, 2005
Messages
8,391
Gender
Male
HSC
2006
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.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 3)

Top