Will an object moving at a constant motion

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    Constant Motion
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Discussion Overview

The discussion centers around the conditions under which an object moving at a constant speed can be launched into orbit. Participants explore the implications of constant speed, gravitational forces, and atmospheric effects on the object's trajectory.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions whether an object moving at a constant speed can be launched into orbit, regardless of the speed and time factors.
  • Another participant states that maintaining a constant speed requires a constant force, while gravity exerts a constant downward acceleration of 9.8 m/s², complicating the situation.
  • A further elaboration notes that the force of gravity decreases with distance from the Earth, suggesting that a decreasing gravitational force could allow for constant speed under certain conditions.
  • It is mentioned that the minimum speed to escape Earth's atmosphere is approximately 11 km/s, with a reference to the kinetic energy equation.
  • One participant argues that if an object moves at constant speed with self-propulsion, it will not enter orbit but will continue to move away from the Earth.
  • Another participant suggests that if the initial speed is sufficiently high, the object could achieve orbit, provided it survives atmospheric drag.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between constant speed and the ability to achieve orbit, with no consensus reached on the conditions necessary for orbital insertion.

Contextual Notes

The discussion includes assumptions about gravitational forces, atmospheric conditions, and the effects of propulsion, which remain unresolved and may influence the conclusions drawn.

noexit1982
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If an object moving at a constant speed be launched into orbit? Irregardless of what that speed is and time not being a factor.
 
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A constant speed requires a constant force to push the object. However, gravity is pulling the object down at a constant acceleration of 9.8m/s^2, and of course air resistance.

The minimum speed to get an object out of the Earth's atmosphere is around 11km/s, according to 0.5mv^2 = GmM/R.
 
A constant speed requires a constant force to push the object. However, gravity is pulling the object down at a constant acceleration of 9.8m/s^2, and of course air resistance.
Actually, since the force of gravity is inversely proportional to the distance r between the center of the Earth and the object, and since the density of the atmosphere also decreases as the distance from Earth increases, a decreasing force will propel an object at a constant speed.

The minimum speed to get an object out of the Earth's atmosphere is around 11km/s, according to 0.5mv^2 = GmM/R.
That's the speed an object must have at (or very close to) the surface of the earth in order to escape Earth's gravitational pull, assuming that no force other than gravity (i.e. no air resistance, no propulsion) acts on the object after it has reached that speed.

If an object moves at constant speed, meaning that it has some means of self-propulsion, it will not go into orbit. It will just keep moving further and further away from the earth.
 
Depends on the aerodyamic drag that occurs until the object gets past the atmosphere, but yes, if the initial speed is high enough, then the object will go into orbit (assuming it doesn't burn up while traveling through the atmosphere).
 

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