
Help me with my homework. YOMAMA
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Re: Help me with my homework. YOMAMA
I would so love to see that on an exam paper. 

God has no place within these walls, just like facts have no place within organized religion. - Superintendent Chalmers
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The Bluebird of Happiness long absent from his life, Ned is visited by the Chicken of Depression. - Gary Larson



Re: Help me with my homework. YOMAMA
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Outside the ordered universe is that amorphous blight of nethermost confusion which blasphemes and bubbles at the center of all infinity—the boundless daemon sultan Azathoth, whose name no lips dare speak aloud, and who gnaws hungrily in inconceivable, unlighted chambers beyond time and space amidst the muffled, maddening beating of vile drums and the thin monotonous whine of accursed flutes.
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- Calilasseia
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Re: Help me with my homework. YOMAMA
It would help if I could see the full text of the questions other than question 1. They look nice and easy.
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Re: Help me with my homework. YOMAMA
I think the missing word is "if".Calilasseia wrote:It would help if I could see the full text of the questions other than quhestion 1. They look nice and easy.
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Re: Help me with my homework. YOMAMA
Ah, of course ... "open image in new tab". Use brain. 
Question 2
Question 2 is nice and easy. Using the standard formula for universal gravitation:
F=GMm/r2
where M is the mass of the larger, gravitating object, and m is the mass of the attracted, accelerating object, r is the distance between the two objects, and G (the value of which is supplied in the question) is Newton's Constant of Universal Gravitation.
Allying this with the standard expression of Newton's Second Law, namely F=ma, we have:
a=GM/r2
We are interested in obtaining M, the mass of Yo Mamma. Algebraic rearrangement gives:
M = ar2/G
Therefore, feeding in those values, we have:
M = 3.74 × 1011 Kg.
Incidentally, if Yo Mamma really was that fat, either she'd be the size of a small asteroid, or she'd be so materially dense, that she'd be in danger of becoming a black hole.
Question 3
Meanwhile, question 3 assumes that we're dealing with circular motion. Under such motion, the standard relation is:
F = mv2/r
where m is the mass of the object in motion, v is the tangential speed of the object, and r is the radius of the circular path. Equating this with F = GMm/r2, we get:
mv2/r = GMm/r2
Cancelling appropriate terms on both sides, we get:
v2 = GM/r
Note that here, r is the distance from the centre of the Earth, toward which the gravitational force is acting.
Rearranging this gives us:
r = GM/v2
In addition, since the flight path is circular, the length of the flight path is 2πr, and therefore the time of one orbital revolution is given by:
T = 2πr/v
This gives us v = 2πr/T. Substituting this into the above expression for v gives us:
r = GMT2 ÷ 4π2r2, or
r3 = GMT2/4π2
This gives us r = 7.1 × 106 m. Feeding that into the expression:
v = 2πr/T
gives us v = 7.4 × 103 m s-1.
As a quick check, the value for r puts the object in Earth orbit at around 763 Km (474 miles) above the Earth's surface, and the orbital speed is around 16,700 mph. These figures are reasonable figures corresponding to those obtained from real low Earth orbit spaceflights.
Enjoy.

Question 2
Question 2 is nice and easy. Using the standard formula for universal gravitation:
F=GMm/r2
where M is the mass of the larger, gravitating object, and m is the mass of the attracted, accelerating object, r is the distance between the two objects, and G (the value of which is supplied in the question) is Newton's Constant of Universal Gravitation.
Allying this with the standard expression of Newton's Second Law, namely F=ma, we have:
a=GM/r2
We are interested in obtaining M, the mass of Yo Mamma. Algebraic rearrangement gives:
M = ar2/G
Therefore, feeding in those values, we have:
M = 3.74 × 1011 Kg.
Incidentally, if Yo Mamma really was that fat, either she'd be the size of a small asteroid, or she'd be so materially dense, that she'd be in danger of becoming a black hole.
Question 3
Meanwhile, question 3 assumes that we're dealing with circular motion. Under such motion, the standard relation is:
F = mv2/r
where m is the mass of the object in motion, v is the tangential speed of the object, and r is the radius of the circular path. Equating this with F = GMm/r2, we get:
mv2/r = GMm/r2
Cancelling appropriate terms on both sides, we get:
v2 = GM/r
Note that here, r is the distance from the centre of the Earth, toward which the gravitational force is acting.
Rearranging this gives us:
r = GM/v2
In addition, since the flight path is circular, the length of the flight path is 2πr, and therefore the time of one orbital revolution is given by:
T = 2πr/v
This gives us v = 2πr/T. Substituting this into the above expression for v gives us:
r = GMT2 ÷ 4π2r2, or
r3 = GMT2/4π2
This gives us r = 7.1 × 106 m. Feeding that into the expression:
v = 2πr/T
gives us v = 7.4 × 103 m s-1.
As a quick check, the value for r puts the object in Earth orbit at around 763 Km (474 miles) above the Earth's surface, and the orbital speed is around 16,700 mph. These figures are reasonable figures corresponding to those obtained from real low Earth orbit spaceflights.
Enjoy.

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Re: Help me with my homework. YOMAMA
No clue what all that meaqns.
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Re: Help me with my homework. YOMAMA
In which case, if this is an actual exam paper you're trying to pass, you're fucked.
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Re: Help me with my homework. YOMAMA
That's my kind of exam paper.Calilasseia wrote:In which case, if this is an actual exam paper you're trying to pass, you're fucked.

Amongst other things, I run the exam papers system at our university, from the point the academics first submit them to central authority to when they get released for public consumption after the exams take place. Some day, I must save all those papers to an external drive for my own use ... I'll search through them for anything "interesting".
God has no place within these walls, just like facts have no place within organized religion. - Superintendent Chalmers
It's not up to us to choose which laws we want to obey. If it were, I'd kill everyone who looked at me cock-eyed! - Rex Banner
The Bluebird of Happiness long absent from his life, Ned is visited by the Chicken of Depression. - Gary Larson

It's not up to us to choose which laws we want to obey. If it were, I'd kill everyone who looked at me cock-eyed! - Rex Banner
The Bluebird of Happiness long absent from his life, Ned is visited by the Chicken of Depression. - Gary Larson



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Re: Help me with my homework. YOMAMA
I always wanted this book:


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- Gawdzilla Sama
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Re: Help me with my homework. YOMAMA
No shit, Sherlock.Calilasseia wrote:In which case, if this is an actual exam paper you're trying to pass, you're fucked.

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