cssa (1 Viewer)

[Matt200]

Just checking that when using the formula to work out gravitational potential energy, you have to include the radius of the planet of which the satelite is circling.

I believe that this years CSSA paper didnt include the radius

 

[ND]

Yep, we had a discussion about it before. You have to use either the formula E=mgh (which isn't stipulated by the syllabus), or sub into newton's law of universal gravitation to determine the radius, and then use the normal eqn. Either way, i think they screwed the question. (not the only screw-up on that paper)

 

[forsaken_99]

Radius is requried, so r=radius +height.

I forgot to put in the radius in the trial and got full marks. I wasn't going to argue with that though.

 

[Rahul]

yep, r=radius+altitude

lol, you cheat!!! you didnt deserve to come first!

jus remember steve, you'll be getting my hsc mark for your school mark

 

[Dash]

They don't normally give you the radius of the Earth

Your required to remember it... arghghghghgh

 

[tooheyz]

Originally posted by Dash
They don't normally give you the radius of the Earth

yeah its on the data sheet - my data sheet anyways

 

[freaking_out]

Originally posted by Dash
They don't normally give you the radius of the Earth

Your required to remember it... arghghghghgh

lol....:rofl:

u might as well remember the gravitational constant.

 

[Rahul]

Originally posted by ToOhEyZ
yeah its on the data sheet - my data sheet anyways

it isnt on the hsc data sheet.

Originally posted by freaking_out
u might as well remember the gravitational constant.

use g=GM/r^2 to work out earth's radius.
use 6.4x10^6 for calculations