What is the terminal velocity of mass falling toward earth?

In summary: Is the maximum velocity of a falling mass 40,200 km/h @ Earth's surface?What do you mean by "the edge of Earth's gravity"??If we imagine a a particle starting at rest at infinity, and then is solely influenced by Earth's gravity, then it will hit Earth with the velocity known as "escape velocity".Perhaps you might call this a "terminal velocity", but that would be an abuse of terms, as Hootenanny has told you already.In summary, the terminal velocity of a mass that falls from the edge of Earth's gravity well to Earth's surface is approximately 40 000 km/h.
  • #1
rwjefferson
16
0
Assume no atmosphere; no friction; no extraneous factors.

What is the terminal velocity of a mass that falls from the edge of Earth's gravity well to Earth's surface?

Thank you in advance for your answer.

Peace
rwj
 
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  • #2
rwjefferson said:
Assume no atmosphere; no friction; no extraneous factors.

What is the terminal velocity of a mass that falls from the edge of Earth's gravity well to Earth's surface?

Thank you in advance for your answer.

Peace
rwj
Terminal velocity by definition requires that there be a drag force. Therefore, no drag force - no terminal velocity.
 
  • #3
rwjefferson said:
Assume no atmosphere; no friction; no extraneous factors.

What is the terminal velocity of a mass that falls from the edge of Earth's gravity well to Earth's surface?

Thank you in advance for your answer.

Peace
rwj
What do you mean by "the edge of Earth's gravity"??

As modeled by classical Newtonian mechanics, the "edge" where there is zero influence from Earth's gravity must be placed infinitely far away from the Earth.

If we imagine a a particle starting at rest at infinity, and then is solely influenced by Earth's gravity, then it will hit Earth with the velocity known as "escape velocity".

Perhaps you might call this a "terminal velocity", but that would be an abuse of terms, as Hootenanny has told you already.
 
  • #4
Is the maximum velocity of a falling mass 40,200 km/h @ Earth's surface?

arildno said:
What do you mean by "the edge of Earth's gravity"??
If we imagine a a particle starting at rest at infinity, and then is solely influenced by Earth's gravity, then it will hit Earth with the velocity known as "escape velocity".
Perhaps you might call this a "terminal velocity", but that would be an abuse of terms, as Hootenanny has told you already.

A plot of gravitational potential of the Earth generates a hyperbolic cross section. The sudden dip in the center is the origin of the name 'gravity well'. The 'edge' of that well occurs where minimal perpendicular velocity counters the force of gravity. I agree that the 'edge' of that well is as arbitrary as 'minimal perpendicular velocity'.

I commend you on your insight.
I will predict that a free-falling mass will reach maximum velocity of 40,200 km/h as it hits the surface of the earth.

Thanks
rwj
 
  • #5


rwjefferson said:
I will predict that a free-falling mass will reach maximum velocity of 40,200 km/h as it hits the surface of the earth.

Thanks
rwj
I'd have to disagree with you there. Your calculations are incorrect.
 
  • #6


Hootenanny said:
I'd have to disagree with you there. Your calculations are incorrect.

What, may I ask, are your better reasons and and calculations that I should doubt equal to escape velocity?

Peace
rwj
 
  • #7


rwjefferson said:
What, may I ask, are your better reasons and and calculations that I should doubt equal to escape velocity?

Peace
rwj
Whoops! I beg your pardon, I thought you had 40 000 km/s.

You are indeed correct, the escape velocity from Earth is indeed approximately 40 000 km/h.

Apologies for the mix-up!
 
  • #8
rwjefferson said:
Assume no atmosphere; no friction; no extraneous factors.

What is the terminal velocity of a mass that falls from the edge of Earth's gravity well to Earth's surface?

Thank you in advance for your answer.

Peace
rwj

It would probably be best that you specified either an object's starting distance from the Earth's surface or a point beginning at a given rate of acceleration m/s^2, as in theory, the further an object is placed from the Earth (and still capable of accelerating towards it), the more time it is given to accelerate and gain a higher end velocity especially considering your "no atmosphere", "no friction", "no extraneous factors" clause. :wink:
 

1. What is terminal velocity?

Terminal velocity is the maximum velocity that an object can reach when falling through a fluid, such as air, due to the balance of gravitational force and air resistance.

2. How is terminal velocity calculated?

The terminal velocity of an object can be calculated using the formula Vt = √(2mg/pAC), where Vt is the terminal velocity, m is the mass of the object, g is the acceleration due to gravity, p is the density of the fluid, A is the cross-sectional area of the object, and C is the drag coefficient.

3. Does the terminal velocity of an object change?

The terminal velocity of an object can change depending on factors such as the density and viscosity of the fluid, the shape and size of the object, and the presence of external forces.

4. What affects the terminal velocity of an object?

The terminal velocity of an object is affected by the object's mass, shape, size, and the properties of the fluid it is falling through. It can also be affected by external forces, such as wind or air currents.

5. How does altitude affect terminal velocity?

Altitude can affect the terminal velocity of an object due to changes in air density. As altitude increases, the air density decreases, resulting in a lower terminal velocity for the object. However, this effect is usually minimal for objects falling from relatively low altitudes.

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