# Section I: Multiple Choice (1 Viewer)

#### Drsoccerball

##### Well-Known Member
I got centripetal and reactant force. This is because if there was only gravity it would fall straight down

#### IamKirby

##### Member
I got centripetal and reactant force. This is because if there was only gravity it would fall straight down
Are you sure? It said stable orbit so I thought that implied it was undergoing centripetal force due to gravity with a constant speed

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##### Member
I got centripetal and reactant force. This is because if there was only gravity it would fall straight down
nah the satellite is kept in place by its velocity not a counter force, centrifugal force is a pseudo force resulting from trying to explain the inertia of objects in a non inertial frame

#### Drsoccerball

##### Well-Known Member
nah the satellite is kept in place by its velocity not a counter force, centrifugal force is a pseudo force resulting from trying to explain the inertia of objects in a non inertial frame
Theres a reaction force for everything so... Anyways its too early lets relax and wait

#### Drsoccerball

##### Well-Known Member
It was alright. It was just that question hahahha. I know for sure I got more than 75%. Really hoping for mid 80%. Some of the multiple choice was definitely iffy. I thought it was harder than previous tests though
Dont underestimate physics HSC marking.

##### Member
Theres a reaction force for everything so... Anyways its too early lets relax and wait
the reaction force is the gravity of the satellite acting on the planet, however because its mass is so small, the effect is negligible
tbh tho i dont think im going to be able to sleep until i get my marks

#### karan96

##### New Member
is anyone gonna upload the paper so we can get mc solutions or nah

#### IamKirby

##### Member
is anyone gonna upload the paper so we can get mc solutions or nah
If you don't have it, why do you expect other people to? Yeah teachers have it, but I don't think their priority is uploading a hsc paper for you which won't at all change your mark.

#### karan96

##### New Member
If you don't have it, why do you expect other people to? Yeah teachers have it, but I don't think their priority is uploading a hsc paper for you which won't at all change your mark.
relax haha, happened for eco so i assumed people might do it here too

#### IamKirby

##### Member
Yeah well in my opinion the way you asked was rude

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apologies mate

#### IamKirby

##### Member
all good, no big deal

#### Drsoccerball

##### Well-Known Member
Nope there is no reaction force on things which are falling
Air resistance....

#### rowcache

##### New Member
Air resistance....
At an altitude of 36000 km? (Geostationary) For our course it would be called negligible.

#### Crisium

##### Pew Pew
Air resistance....
I thought of it in regards to projectile motion because I read of an example where they say the rocket used to launch a satellite into space will not make it a projectile (since it's being propelled with the constant thrust force) BUT when it runs out of fuel then it becomes a projectile --> As we all know the only force acting on a projectile is gravity so yeah

gg no re to my crappy reasoning - Some aspects of multiple choice killed me but the SA and option were good

#### Crisium

##### Pew Pew
Air resistance....
Atmosphere only extends for about 200 - 400 km about the earths surface so it's more likely to affect a low earth orbit satellite

#### Drsoccerball

##### Well-Known Member
There goes another mark

#### rand_althor

##### Active Member
is anyone gonna upload the paper so we can get mc solutions or nah
lol woops threw my copy away with all the rest of my HSC stuff. I think Fizzy_Cyst might upload it if he manages to get a paper.

I got :
1)C
2)B
3)B
4)D
5)A
6)B
7)C
8)C
9)B
10)A
11)C
12) D
13)C
14) C
15) A
16)C
17)A
18)A
19)C
20)B