Calculating Escape Velocity on the Equator: Is It Possible?

In summary, the equator is a good location for calculating escape velocity because the distance from the Earth's surface to the centre is the greatest at the equator.
  • #1
blost
14
0
hello... I've got some small problem with Escape velocity. So... is it dependent on geographic coordinate ? I suppose "Yes!"... but is it true?

Using conservation of energy, I calculate this velocity on equator this way:

[tex]\frac{mv^2}{2}= \frac{GMm}{R} - \frac{m(2 \pi R)^2}{T^2*R }[/tex]
Am I right ?
 
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  • #2
blost said:
hello... I've got some small problem with Escape velocity. So... is it dependent on geographic coordinate ? I suppose "Yes!"... but is it true?

Using conservation of energy, I calculate this velocity on equator this way:

[tex]\frac{mv^2}{2}= \frac{GMm}{R} - \frac{m(2 \pi R)^2}{T^2*R }[/tex]
Am I right ?
Are you trying to take into account the speed of the escaping object when it is sitting on the earth? Why?

To escape the earth, the object has to have enough kinetic energy so that its total energy (kinetic + potential) is greater than 0.

Condition for escape: KE + PE > 0.

AM
 
  • #3
blost said:
hello... I've got some small problem with Escape velocity. So... is it dependent on geographic coordinate ? I suppose "Yes!"... but is it true?

Using conservation of energy, I calculate this velocity on equator this way:

[tex]\frac{mv^2}{2}= \frac{GMm}{R} - \frac{m(2 \pi R)^2}{T^2*R }[/tex]
Am I right ?

You've assumed that your escaping mass is locked in a circular orbit around the earth, that is completely incorrect.
I also don't think you're comparing any actual energies of the object. What two states are you comparing? Try and compare the state where it's released from the surface of the earth, and the one when it has escaped it (It is no longer influenced by Earth's gravitational field, what does that mean energy-wise?)

Read Andrew Mason's pointers, they should help you get started, and you should then see whether the solution depends on your initial position or not.
 
Last edited:
  • #4
I know that KE+Pe>0.
And I know that escaping mass isn't locked in a circular orbit around the earth, but it's still got a kinetic energy from Earth rotation, so i don't know, is Kinetic energy a sum of kinetic energy of Earth rotation and energy which must be inserted to this object?
 
  • #5
blost said:
I know that KE+Pe>0.
And I know that escaping mass isn't locked in a circular orbit around the earth, but it's still got a kinetic energy from Earth rotation, so i don't know, is Kinetic energy a sum of kinetic energy of Earth rotation and energy which must be inserted to this object?
Yes, of course. But the question asks for the escape velocity, not the velocity or energy that you must add in order to achieve the escape velocity.

The reason the equator is important in this question is this: the distance from the Earth's surface to the centre varies with latitude. It is greatest at the equator.

AM
 
  • #6
Andrew Mason said:
Yes, of course. But the question asks for the escape velocity, not the velocity or energy that you must add in order to achieve the escape velocity.

thanks. Now i know...

by the way... sorry for my not-recherche language. English is not my native language (I'm 17 from Poland-3 h eng for a week ;/ 37 people in my class ;/ as like Cambodia... ), so please be tolerate :)
 

1. What is escape velocity and how is it calculated?

Escape velocity is the minimum speed needed for an object to escape the gravitational pull of a larger object, such as a planet or moon. It is calculated using the formula v = √(2GM/r), where G is the universal gravitational constant, M is the mass of the larger object, and r is the distance from the center of the object to the center of the smaller object.

2. Is it possible to calculate escape velocity on the equator?

Yes, it is possible to calculate escape velocity on the equator. The equator is simply a location on the surface of a planet or moon, so the same formula for escape velocity can be used.

3. How does the rotation of the Earth affect escape velocity on the equator?

The rotation of the Earth does not have a significant effect on the escape velocity on the equator. While the Earth's rotation does affect the overall velocity of an object, the effect is very small compared to the large mass of the Earth.

4. Is escape velocity on the equator different from other locations on Earth?

No, escape velocity on the equator is the same as other locations on Earth. The difference in distance from the center of the Earth to the center of the object is negligible, so the same escape velocity formula can be used.

5. Can escape velocity on the equator be affected by other factors?

Yes, other factors such as the atmospheric conditions and the presence of other objects near the equator can affect the escape velocity. However, these effects are typically small and can be accounted for in the calculations.

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