1. I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S

2.

3. Originally Posted by Captain_Anubis
I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S
It definately is escape volocity not acceleration. Its the velocity needed for your mass(m2) to travel so that the gravity of m1 curves the path of your mass less than the curvature of the surface of m1.

4. if a object with mass m have 0 in PE and V=0 at infinite distance from another object with amss M it have will have the potensial energy -GMm/R at distance R
using some classic stuff that EK = mV²/2
and because energy cant come from nowhere, exept in QM, EK+PE must allways be the same aslongest nothing else takes it.
with our writing its mV²/2-GMm/R = 0 because it didnt have any KE or PE in the begining
some rearangement we get
mV²/2=GMm/R
little more rearangement
V=sqr(2GM/R)
this have all to do with the law of energy conservation not acceleratoin. u can also see that the mass of the object leaving doesnt effect it.
but if u know the mass of the oibject m u can calculate the thrust needed by using impulse law
I=FT=dP=m*dv=m*V
then divide it with the time wich it takes and u´ll get the minimum amount of netforce required to get it into outer space. but notice its the netforce, to get the total amount of force u´ll have to take F+mg

5. Originally Posted by Imaplanck.
Originally Posted by Captain_Anubis
I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S
It definately is escape volocity not acceleration. Its the velocity needed for your mass(m2) to travel so that the gravity of m1 curves the path of your mass less than the curvature of the surface of m1.
Ok, so it's how fast you have to be moving along the surface of Earth to force yourself into orbit... cool ^^

6. Originally Posted by Captain_Anubis
Originally Posted by Imaplanck.
Originally Posted by Captain_Anubis
I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S
It definately is escape volocity not acceleration. Its the velocity needed for your mass(m2) to travel so that the gravity of m1 curves the path of your mass less than the curvature of the surface of m1.
Ok, so it's how fast you have to be moving along the surface of Earth to force yourself into orbit... cool ^^
Yes its like you are always moving in a straight line but when you are under the gravitational influence of another mass(the earth for instance) the space around that mass is distorted so your path is essentially curved, the amount of curve is dependent on your velocity not acceleration.

7. Originally Posted by Captain_Anubis
Originally Posted by Imaplanck.
Originally Posted by Captain_Anubis
I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S
It definately is escape volocity not acceleration. Its the velocity needed for your mass(m2) to travel so that the gravity of m1 curves the path of your mass less than the curvature of the surface of m1.
Ok, so it's how fast you have to be moving along the surface of Earth to force yourself into orbit... cool ^^
that is just stupid. no its the speed u need straight up. 90° from the land. and this is not the speed for ORBIT. its the speed equired to LEAVE earth enterily. with orbit u need it to be less. if u want i can write that formula aswell

8. Originally Posted by Zelos
Originally Posted by Captain_Anubis
Originally Posted by Imaplanck.
Originally Posted by Captain_Anubis
I don't understand the concept of escape velocity. It's supposed to be the minimum speed at which you must move in order to escape some mass with a gravitational force. The way i see it is shouldn't it be more of an escape acceleration?? If you could get an engine that pushed some 1kg mass with 10N up for a second and then reduced to exactly G and stayed at whatever G is at any distance from Earth wouldn't that get you off of the planet with a velocity of next to nothing?? Or an I misunderstanding the concept.. :S
It definately is escape volocity not acceleration. Its the velocity needed for your mass(m2) to travel so that the gravity of m1 curves the path of your mass less than the curvature of the surface of m1.
Ok, so it's how fast you have to be moving along the surface of Earth to force yourself into orbit... cool ^^
that is just stupid. no its the speed u need straight up. 90° from the land.
No its not completely stupid! If you imagine the earth as a completely smooth sphere with no atmosphere and you speed along the surface at the escape velocity and you maintain that velocity indefinately you will eventually escape. Its not dependant on being perpendicular to earth, if you are in orbit and accelerate to escape velocity you will escape, Parallel, perpendicular or anywhere in between - THE ESCAPE VELOCITY IS THE SAME. C anubis made a valid analogy.

9. im ready to bet my ass that it doesnt matter what planet u leave from with a significan earthlike size would result in disaster if u did it with 00°, of course 90° but when i think on it, ure right, my bad

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