What if inertial mass did NOT = grav. mass?

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SUMMARY

The discussion centers on the hypothetical scenario where inertial mass does not equal gravitational mass, exploring the implications for daily life and physics. Participants highlight that if these masses were not equivalent, the fundamental laws of motion and gravity would change, leading to phenomena such as heavier objects falling faster than lighter ones. The conversation references the equivalence principle and experiments like the Eöt-Wash experiment, which confirm the equality of inertial and gravitational mass to a high degree of precision. Theoretical implications include altered dynamics in activities like walking and throwing objects, fundamentally changing our understanding of motion.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with the equivalence principle in physics
  • Basic knowledge of gravitational and inertial mass
  • Awareness of experimental physics, particularly the Eöt-Wash experiment
NEXT STEPS
  • Research the Eöt-Wash experiment and its significance in confirming mass equivalence
  • Explore the implications of the equivalence principle in general relativity
  • Study the effects of varying gravitational fields on object motion
  • Investigate the theoretical consequences of non-equivalent inertial and gravitational mass
USEFUL FOR

Physicists, students of physics, and anyone interested in the fundamental principles of motion and gravity will benefit from this discussion.

  • #91
Noted Jorrie. It's an interesting one this. That 2a means the falling is faster, but dropping two objects also says it isn't. Hmmn.

I wonder if the Earth would have a different orbit if the moon wasn't there?
 
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  • #92
Farsight said:
Noted Jorrie. It's an interesting one this. That 2a means the falling is faster, but dropping two objects also says it isn't. Hmmn.

I wonder if the Earth would have a different orbit if the moon wasn't there?

I think there would have been a minor difference - instead of the Earth cycling around the Earth-Moon baricentre every 28 days or so, the Earth would have had a more standard elliptical orbit around the Sun.

IMO, the crucial point is that the mass of the orbiting object has negligible effect on the orbit, as long as its mass is small compared to the primary mass (the Sun in this case). So the Earth-Moon baricentre follows an orbit that is roughly independent of the mass of the Earth-Moon system.
 
  • #93
Thanks Jorrie.
 

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