Mass of the Earth Traveling at 500,000 mph?

  • Thread starter Thread starter Uberhulk
  • Start date Start date
  • Tags Tags
    Earth Mass
Click For Summary
The discussion centers on the hypothetical scenario of a planet with Earth's mass traveling at 500,000 mph. Relativistic effects at this speed are negligible, as they only become significant at a substantial fraction of the speed of light. The conversation explores the immense force required to stop such a planet, highlighting that stopping it in a short time frame would result in unrealistic pressures and forces far exceeding material limits. Participants acknowledge the comic book context, where physics can be disregarded for storytelling purposes, yet they engage in calculations to illustrate the absurdity of the scenario. Ultimately, the thread emphasizes the blend of science and fiction, questioning the feasibility of lifting or stopping a planet under these conditions.
  • #31
DaveC426913 said:
Doesn't the mass of two Earths create twice as strong an attraction as one Earth? Is that not why - when we measure the acceleration of things on Earth - we must drop a test object of negligible mass, so that its own gravity does not skew the measurement?
Force attracting two Earth masses with their centers 1 Earth radius apart ~ 6.673e-11 (6e24)^2/6378000^2 = ~5.9e25 N. Force needed to accelerate one Earth mass at 9.81 m/sec/sec ~ 6e24* 9.81 = 5.9e25 N.
 
  • Like
Likes DaveC426913
Physics news on Phys.org
  • #32
Janus said:
Force attracting two Earth masses with their centers 1 Earth radius apart ~ 6.673e-11 (6e24)^2/6378000^2 = ~5.9e25 N. Force needed to accelerate one Earth mass at 9.81 m/sec/sec ~ 6e24* 9.81 = 5.9e25 N.
Two adjacent Earths with radius equal to one Earth radius will have their centers two Earth radii apart.

Agreed, though that the force is not doubled. Newton's third law still holds.
 
  • #33
jbriggs444 said:
Two adjacent Earths with radius equal to one Earth radius will have their centers two Earth radii apart.

Agreed, though that the force is not doubled. Newton's third law still holds.
I was considering a "Earth equivalent" mass being supported at the surface of the Earth, not two Earth-sized objects.
 
  • Like
Likes jbriggs444

Similar threads

Writing: Input Wanted How would an Earth-like Planet fair with a Uranus like moon system?
  • · Replies 3 ·
Replies
3
Views
244
The Science of Interstellar: Tidal Wave
  • · Replies 5 ·
Replies
5
Views
4K
Building a Planet: Considerations for a Habitable Solar System
  • · Replies 2 ·
Replies
2
Views
2K
B If Earth moves at 500,000 mph then why don't satellites stay behind?
  • · Replies 18 ·
Replies
18
Views
3K
I What was the role of frequency in the Michelson-Morley experiment's null result?
  • · Replies 3 ·
Replies
3
Views
1K
Can the Federation interfere in other planets' affairs in Star Trek?
  • · Replies 40 ·
2
Replies
40
Views
4K
B What if we use a non physical reference point to measure an object's mass?
  • · Replies 5 ·
Replies
5
Views
1K
I Atomic Clock Speed graph between two stationary masses
  • · Replies 23 ·
Replies
23
Views
2K
I New Developments In The Search For Planet X
  • · Replies 2 ·
Replies
2
Views
3K
How Would a Red Dwarf Companion Affect Our Sunset Views?
  • · Replies 41 ·
2
Replies
41
Views
7K