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HSC Physics Predictions / Thoughts (2 Viewers)

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My teacher said D
think about it right: the ball has two components of velocity, one that is tangential to the curve's surface and another that goes up or down the curve vertically. the up/down velocity isnt going to induce centripetal force off the wall bc its not in circular motion, only the horizontal tangential velocity is
 

idkkdi

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think about it right: the ball has two components of velocity, one that is tangential to the curve's surface and another that goes up or down the curve vertically. the up/down velocity isnt going to induce centripetal force off the wall bc its not in circular motion, only the horizontal tangential velocity is
if the magnitude of the net force was constant, wouldn't the ball be travelling in a circular path? Yet, the object is clearly not travelling in a circular path.

there's something wrong about this argument I have stated, but I can't quite see where. help.

I think the way to go about this question, is also, to ignore everything in the z-axis.
 
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if the magnitude of the net force was constant, wouldn't the ball be travelling in a circular path? Yet, the object is clearly not travelling in a circular path.

there's something wrong about this argument I have stated, but I can't quite see where. help.

I think the way to go about this question, is also, to ignore everything in the z-axis.
ok so heres the deal: if you stretched the wall out, the path of the ball would make a parabolic line against the wall, but horizontal (tangential) velocity is gonna be the same the whole way thru, just as in projectile motion. it is that tangential velocity that creates a normal (centripetal) force, the vertical velocity doesnt create any normal force therefore it wont matter
 

idkkdi

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ok so heres the deal: if you stretched the wall out, the path of the ball would make a parabolic line against the wall, but horizontal (tangential) velocity is gonna be the same the whole way thru, just as in projectile motion. it is that tangential velocity that creates a normal (centripetal) force, the vertical velocity doesnt create any normal force therefore it wont matter
actually it makes sense nvm. Take the parabolic path as it is, tilt it, such that it becomes the new plane on flat ground. Now taking the component of gravity, which acts in this plane, which then allows for the elliptical path to be taken, assuming that net force, excluding gravity, is constant. This is because as theta between the net force and gravity component vector varies (in the process of vector addition), it eventually reaches maximimum centripetal force at where r becomes the smallest.

if you don't understand what I wrote don't bother. I can't be bothered to explain it tbh.
 
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Speed’o’sound Sonic

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actually it makes sense nvm. Take the parabolic path as it is, tilt it, such that it becomes the new plane on flat ground. Now taking the component of gravity, which acts in this plane, which then allows for the elliptical path to be taken, assuming that net force, excluding gravity, is constant. This is because as theta between the net force and gravity component vector varies (in the process of vector addition), it eventually reaches maximimum centripetal force at where r becomes the smallest.

if you don't understand what I wrote don't bother. I can't be bothered to explain it tbh.
Sorry bro gotta back homeworkatemydog here
 

Speed’o’sound Sonic

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what did you write for the 9 marker and 7 marker
For the motor pulling a mass I talked about factors influencing torque on the pulley (current, magnetic field strength, area and number of armature coils, etc
what did you write for the 9 marker and 7 marker
For the motor pulling a mass I talked about factors influencing torque on the pulley (current, magnetic field strength, area and number of armature coils, etc, and distance between rotor and pulley edge, as well as factors influencing friction on the mass I.e coefficient of friction and weight of the mass. For the standard model question I talked about how proton is a hadron + Baryon and how the electron is a lepton and examined the force carriers and their effects on the H atom.
 

Speed’o’sound Sonic

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do you think maybe more like 87-88 coz chem last year scaled 90 -> 95 and that was a pretty easy exam and physics scales better than chem.
Im not sure, just trying to get an estimate :) I try to low ball it as to remain as realistic as possible. It was a difficult exam, so a score of 88 could well moderate to 95 ‘MAYBE’
 

Luke322

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For the motor pulling a mass I talked about factors influencing torque on the pulley (current, magnetic field strength, area and number of armature coils, etc

For the motor pulling a mass I talked about factors influencing torque on the pulley (current, magnetic field strength, area and number of armature coils, etc, and distance between rotor and pulley edge, as well as factors influencing friction on the mass I.e coefficient of friction and weight of the mass. For the standard model question I talked about how proton is a hadron + Baryon and how the electron is a lepton and examined the force carriers and their effects on the H atom.
damn for the standard model question I wrote about electrons being leptons and protons being baryons but I didn't talk about their effects on the H atom
 

Speed’o’sound Sonic

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damn for the standard model question I wrote about electrons being leptons and protons being baryons but I didn't talk about their effects on the H atom
Well I mean the question asked about the H atom specifically. It’d be good to talk about how the lepton orbited the Baryon nucleus because of electrostatic and weak nuclear forces but that’s ok
 

Luke322

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Oh yeah also what did you say for the question asking you to derive the speed of B. 31 b) I think it was with the gravitational force between planets A and B where the speed of A was constant
 

Speed’o’sound Sonic

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Oh yeah also what did you say for the question asking you to derive the speed of B. 31 b) I think it was with the gravitational force between planets A and B where the speed of A was constant
Yeah you used Grav force then just K = 1/2 m v^2 or something like that. Can’t remember specifically but there was hypothetically a second scenario where the planets are infinitely far away from one another and their speed cannot be determined. Not sure if that’ll be in the question though
 

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