Author Topic: Physics help A2  (Read 2765 times)

nid404

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Re: Physics help A2
« Reply #15 on: July 28, 2010, 03:52:42 pm »
oooh yeah right, I get it now. Thanks. :)

That's what I think it is...anytime (:

Alpha

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Re: Physics help A2
« Reply #16 on: July 29, 2010, 08:35:16 am »
Adi has the MS?

nid404

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Re: Physics help A2
« Reply #17 on: July 29, 2010, 02:12:26 pm »

Alpha

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Re: Physics help A2
« Reply #18 on: July 29, 2010, 02:15:24 pm »
1.7 is right

Sure? When I saw it was Physics, I became unsure... lol

By the way, thanks.  ;)

nid404

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Re: Physics help A2
« Reply #19 on: July 29, 2010, 06:30:06 pm »
Anytime :)

Offline sizbeauty

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gravitation ques prob!!
« Reply #20 on: September 19, 2010, 05:48:01 pm »
Q1,find the speed of the satellite which orbitz the moon near the moon's curface?
what is the kinetic energy per unit mass of the satellite?
(radius of moon: 1.74*10^6,mass of moon: 7.35*10^22)

Q2,astronomical observationz show the centre of mass of the earth-moon system is 4.7*10^6 m frm the centre of the earth.the distance b/w the centre of the earth n the moon is 384.4*10^6 m.find the mass of the moon M in terms of the mass of the earth E.
explain why both earth n moon must rotate about their common centre of mass,rather than the moon abot the centre of mass of the earth.

nid404

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Re: gravitation ques prob!!
« Reply #21 on: September 19, 2010, 05:59:03 pm »
Q1,find the speed of the satellite which orbitz the moon near the moon's curface?
what is the kinetic energy per unit mass of the satellite?
(radius of moon: 1.74*10^6,mass of moon: 7.35*10^22)

Q2,astronomical observationz show the centre of mass of the earth-moon system is 4.7*10^6 m frm the centre of the earth.the distance b/w the centre of the earth n the moon is 384.4*10^6 m.find the mass of the moon M in terms of the mass of the earth E.
explain why both earth n moon must rotate about their common centre of mass,rather than the moon abot the centre of mass of the earth.

Mass of the satellite? :\

Do you have the entire question? Is it from a past paper?

Offline sizbeauty

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Re: Physics help A2
« Reply #22 on: September 19, 2010, 06:13:27 pm »
this is the entire ques!!
itz frm unsolved topical pastpaperz,this one is frm year Nov88/p2/Q3.
do u have dese pastpprz??

nid404

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Re: Physics help A2
« Reply #23 on: September 19, 2010, 06:16:58 pm »
In the first question, the gravitation pull provides the necessary centripetal force. So you equate the two

GMm/ r2= mv2/r

You get v.

The second half, I don't really get it. The mass of the satellite ain't mentioned...I can't figure that.

Offline sizbeauty

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Re: Physics help A2
« Reply #24 on: September 19, 2010, 06:19:30 pm »
ok np!! :)
thanx for de help,you r the saver!!  :)

nid404

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Re: Physics help A2
« Reply #25 on: September 19, 2010, 06:21:24 pm »
The second question. At 4.7*10^6 m frm the centre of the earth. the gravitational pull on any objects would be 0 apparently.

So.

GM/ (4.7*10^6)2= GM2(mass of the moon)/ (384.4*10^6 - 4.7*10^6)2

You get M2.

I don't get the second half of this one either :\

Offline sizbeauty

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Re: Physics help A2
« Reply #26 on: September 19, 2010, 06:27:41 pm »
hehe itz ok!!  ;D
i ll let u knw de scnd part of both dese ques if i becum smart enough to get thm frm ma teacher'z xplanation!! :P
thanx alot once again!! :)