Difference between Mass and Weight?

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SUMMARY

The discussion clarifies the distinction between mass and weight, emphasizing that mass is the amount of matter in an object and remains constant regardless of location, while weight is the gravitational force exerted on that mass by Earth or another celestial body. For example, an object retains the same mass on the Moon but experiences only 1/6 of its Earth weight due to reduced gravitational pull. The conversation also highlights the concept of apparent weight, which refers to the sensation of weightlessness experienced in free-fall situations, such as in a falling elevator or during skydiving.

PREREQUISITES
  • Understanding of Newton's second law of motion
  • Basic knowledge of gravitational forces
  • Familiarity with concepts of mass and weight
  • Awareness of the effects of gravity on different celestial bodies
NEXT STEPS
  • Research the implications of Newton's second law in various physical scenarios
  • Explore the differences between mass and weight in different gravitational fields
  • Study the concept of apparent weight in free-fall conditions
  • Investigate the effects of gravity on objects in space versus on Earth
USEFUL FOR

Students of physics, educators teaching basic science concepts, and anyone interested in understanding the fundamental principles of mass and weight in relation to gravity.

Jadaav
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What is the difference between Mass and Weight?

Because i often get confused about it.

It's concerned about Newton's second law.

I'm trying to learn it by myself.:)
 
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Mass is how much stuff there is in an object - it doesn't change.
Weight is the force that the Earth pulls on the mass with.

So on the moon you would have the same mass, but only 1/6 the weight.
In a falling elevator you would be weightless but not massless.
 
mgb_phys said:
Weight is the force that the Earth pulls on the mass with.
In a falling elevator you would be weightless but not massless.
These are two rather distinct definitions of weight. The gravitational force that the Earth exerts on a person in a falling elevator is no different than the force that the Earth exerted on this unfortunate person while he was waiting for the elevator. In this context, weight is just a synonym for gravitational force.

We call the person in the falling elevator "weightless" because that person truly does feel something quite different than the person waiting for the elevator. The same feeling of weightlessness occurs when a skydiver first jumps out of an airplane and when an astronaut is in a quiescent (non-thrusting) orbiting vehicle. That second definition of weight is called apparent or scale weight.

Finally, legally and colloquially, weight is a synonym for mass rather than having units of a force. In this context, a one pound can of peas weighs one pound anywhere on the Earth, in a space station, on the Moon, and in deep space.
 
Thanks for the answers guys:)
 
mgb_phys said:
Weight is the force that the Earth pulls on the mass with.

Some discrepancy here:

So on the moon you would have the same mass, but only 1/6 the weight.

Assuming it is force that Earth pulls me with, when on Moon surface I should weight much less than that, about 1/3640 :-p
 

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