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Newtons Law of Gravitation and Satellites (1 Viewer)
- Thread starter bobmaza
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gordo
Resident Jew
wats newtons law of gravitation?
that objects regardless of mass fall at the same rate?
lol i have physics in 4 days, i should know this
that objects regardless of mass fall at the same rate?
lol i have physics in 4 days, i should know this
newtons law of gravitation:: ok well since i have nothing better to do [and didnt get thanked on the SDD board] i figure ill ggo out of my way to help..
Isaac Newton compared the acceleration of the moon to the acceleration of objects on earth. Believing that gravitational forces were responsible for each, Newton was able to draw an important conclusion about the dependence of gravity upon distance.
He figured out that the force of gravitational attraction between the Earth and other objects is inversely proportional to the distance separating the earth's center from the object's center. This is IMPORTANT Remember its to CENTER of Earth!!!
Distance is NOT the only variable that determines force due to gravity, this lead to his formula:
F = ma
(you should SOOOO know this)
He also discovered that gravitation is universal. ALL objects attract each other with a force of gravitational attraction. Hence the F = (GM1M2) / r 2
The Value of 'G' [the universal constant] however was not discovered by newton but by some other random, but using his work.. u want more info?!
Isaac Newton compared the acceleration of the moon to the acceleration of objects on earth. Believing that gravitational forces were responsible for each, Newton was able to draw an important conclusion about the dependence of gravity upon distance.
He figured out that the force of gravitational attraction between the Earth and other objects is inversely proportional to the distance separating the earth's center from the object's center. This is IMPORTANT Remember its to CENTER of Earth!!!
Distance is NOT the only variable that determines force due to gravity, this lead to his formula:
F = ma
(you should SOOOO know this)
He also discovered that gravitation is universal. ALL objects attract each other with a force of gravitational attraction. Hence the F = (GM1M2) / r 2
The Value of 'G' [the universal constant] however was not discovered by newton but by some other random, but using his work.. u want more info?!
smallcattle
Member
newtons law of gravitation stated that any two objects exerts gravitational force of attraction on each other. the magnitude of the force is proportionally to the product of the gravitational forces of the objects, and inversely porportionally to the square of the distance between themgordo said:
The Bograt
boredofuni
The Law helps us understand that the required velocity for a satellite to remain in a certain orbit is dependent only upon the mass of the planet it is orbiting and its distance from the centre of that planet (or other body).
*Insert incorrect buzzer here*, my quote when i MENTIONED them required you to understand newtons law of gravitation, His law does NOT explain orbital velocity.. That, my friend, would have been our great mathematician: Tsiolovsky [Spelling?]The Bograt said:
But good luck anyway
gordo
Resident Jew
oh yeh lol
gallileo postulated wat i said about masses falling at the same rate
yeh, newton said any two masses will exert a force on each other. hence for escape velocity u set the zero point infinite distance away and just look at it as its ratio of the decrease of its initial velocity with the decrease of the pull of the planet as it gets furthere awya, these both decrease at an equal ratio, thus the object will travel forever and hypothetically escape gravity at infinity
gallileo postulated wat i said about masses falling at the same rate
yeh, newton said any two masses will exert a force on each other. hence for escape velocity u set the zero point infinite distance away and just look at it as its ratio of the decrease of its initial velocity with the decrease of the pull of the planet as it gets furthere awya, these both decrease at an equal ratio, thus the object will travel forever and hypothetically escape gravity at infinity
The Bograt
boredofuni
Grrrr they are from notes I got from the guy first in my year, I will inform him of the errorJayWalker said:*Insert incorrect buzzer here*, my quote when i MENTIONED them required you to understand newtons law of gravitation, His law does NOT explain orbital velocity.. That, my friend, would have been our great mathematician: Tsiolovsky [Spelling?]
But good luck anyway
Thanks
Tis kewl, Re-read those notes, If he states that orbital velocity is icluded in Newtons Law of Gravity, then thats wrong.
I believe [dont quote me on this] but wasnt Newton the one with the idea of the Great Big Cannon, and he said it was impossible because the velocity required would be too great and the forces required were [well for lack of a better word] just totally stupid / befuggling / too big / unbelieveable... etc etc...
But if you look at Tsiolovsky, he was the first person to mathematically find an equation that related orbital velocity to distance, and mass of the planet..
If the notes say the orbital velocity was a RESULT of Newtons Law of Gravity, well anything in space is... so he was sorta right
I believe [dont quote me on this] but wasnt Newton the one with the idea of the Great Big Cannon, and he said it was impossible because the velocity required would be too great and the forces required were [well for lack of a better word] just totally stupid / befuggling / too big / unbelieveable... etc etc...
But if you look at Tsiolovsky, he was the first person to mathematically find an equation that related orbital velocity to distance, and mass of the planet..
If the notes say the orbital velocity was a RESULT of Newtons Law of Gravity, well anything in space is... so he was sorta right
CrashOveride
Active Member
You just equate the the law of universal attraction with centripetal force and you get your orbital velocity. I dont think Newton actually did that but it was as a result of his law.
Did Newton suggest the cannon? I know he talked about it fired from the top of a mountain in his escape velocity but yeah essentially by firing something wiht an initial velocity so great, the huge acceleration would produce g-forces that wud kill any living thing or damage equipment.
Did Newton suggest the cannon? I know he talked about it fired from the top of a mountain in his escape velocity but yeah essentially by firing something wiht an initial velocity so great, the huge acceleration would produce g-forces that wud kill any living thing or damage equipment.
Constip8edSkunk
Joga Bonito
well newton's though experiment, as recorded, was based on the cannon...such details are trivial anyway...yeh newton did say it was impossible, though didnt stop jules verne writing a book about it...
for dot pts like these, you'll need to relate to many other ones. so here (along with several other pts in this section) , you'll need to understand how F=GMm/r^2 is used in working out all the characteristics of the motion of satellites, not just the relation between force, mass and distance as the eqn explicitly states, i think.
and yeah so i reckon u need to talk about more than what newton actually did, but also the implications of what he did, things like equating with centripetal force; substitution to get angular velocities etc, which are also under a couple of other dot pts
for dot pts like these, you'll need to relate to many other ones. so here (along with several other pts in this section) , you'll need to understand how F=GMm/r^2 is used in working out all the characteristics of the motion of satellites, not just the relation between force, mass and distance as the eqn explicitly states, i think.
and yeah so i reckon u need to talk about more than what newton actually did, but also the implications of what he did, things like equating with centripetal force; substitution to get angular velocities etc, which are also under a couple of other dot pts