Explaining Escape Velocity: Zero KE and PE at r=infinite

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SUMMARY

The discussion centers on the concept of escape velocity, specifically addressing the conditions at infinite distance (r=infinite). It is established that an object achieving escape velocity will have zero kinetic energy (KE) and potential energy (PE) at that point. The kinetic energy decreases as the object moves away from the gravitational field, ultimately reaching zero when the potential energy also reaches zero. This relationship underscores that escape velocity is the minimum speed required to overcome gravitational forces without further acceleration.

PREREQUISITES
  • Understanding of gravitational potential energy (PE) and kinetic energy (KE)
  • Familiarity with the concept of escape velocity in classical mechanics
  • Basic knowledge of limits in physics
  • Comprehension of gravitational fields and their effects on objects
NEXT STEPS
  • Study the mathematical derivation of escape velocity in classical mechanics
  • Explore the relationship between kinetic energy and potential energy in gravitational fields
  • Investigate the implications of escape velocity in astrophysics
  • Learn about the effects of additional forces on objects achieving escape velocity
USEFUL FOR

Students of physics, educators teaching mechanics, and anyone interested in understanding the principles of escape velocity and gravitational interactions.

yasar1967
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Escape Velocity:
"An object given the escape speed will have zero kinetic energy at r=infinite, and the potential energy is defined to be zero at that point, so the total energy is 0"

I understand having zero potential energy at infinite distance but I do not correlate with having zero kinetic energy. Once you have given that escape velocity to the object it must have always that speed even even at the infinity unless another force is applied. So how could it be that it's kinetic energy will be zero?
 
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The kinetic energy decreases to zero as the potential decreases to zero (because it is accelerating, against gravity). Gravity causes it to decrease (i.e. the escape velocity is the minimum needed to escape the field). Just a case of a limit.
 

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