Why Won't a Space Probe with 3GMm/R Energy Escape Earth's Gravity?

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SUMMARY

The discussion centers on the energy required for a space probe to escape Earth's gravity, specifically analyzing the equation E=(3GMm/R). Despite the probe having three times the minimum kinetic energy needed, represented as -GMm/R, participants conclude that it will not escape into deep space. The confusion arises from the misunderstanding of gravitational potential energy and the influence of other celestial bodies, such as the Sun, on the probe's trajectory.

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Homework Statement



A space probe is launched from the equator in the direction of the north pole of the Earth. During launch the energy given to the probe of mass m is

E=(3GMm/R)

Deduce that the Space probe will not be able to travel into deep space

Homework Equations



Minimum KE needed = - GMm/R

The Attempt at a Solution



I said that if minimum KE was as above then having three times that would mean that it would escape but the answer is that it won't so I'm puzzled? How do I deduce that it won't escape if it has 3 times the energy E=(3GMm/R)
 
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Should it have a negative sign in front of it, I remember something bout infinity? Please help!

confused200 said:

Homework Statement



A space probe is launched from the equator in the direction of the north pole of the Earth. During launch the energy given to the probe of mass m is

E=(3GMm/R)

Deduce that the Space probe will not be able to travel into deep space

Homework Equations



Minimum KE needed = - GMm/R

The Attempt at a Solution



I said that if minimum KE was as above then having three times that would mean that it would escape but the answer is that it won't so I'm puzzled? How do I deduce that it won't escape if it has 3 times the energy E=(3GMm/R)
 
hmm. You're right, that the probe should be able to completely escape from the Earth's gravitational field... Maybe you are also supposed to take into account the gravitational field from the sun?...
 

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