Gravity Questions: Explaining Why Mass Doesn't Matter When Free Falling

  • Context: Undergrad 
  • Thread starter Thread starter misogynisticfeminist
  • Start date Start date
  • Tags Tags
    Gravity
Click For Summary
SUMMARY

The discussion centers on the principles of gravity, specifically addressing why mass does not affect the acceleration of free-falling objects. The user equates Newton's second law, F=ma, with the gravitational force equation, F=\frac {Gm_1m_2}{D^2}, noting that the masses cancel out. It is confirmed that m_2 represents the mass of the Earth, and the distance D refers to the distance from the Earth's center to the object. The conclusion emphasizes that the gravitational acceleration remains constant regardless of the object's mass when near the Earth's surface.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with gravitational force equations
  • Knowledge of gravitational acceleration (g)
  • Basic concepts of Earth's mean radius
NEXT STEPS
  • Study the implications of Galileo's experiments on gravity
  • Explore the derivation of gravitational force equations
  • Learn about Cavendish's constant and its significance in gravitational calculations
  • Investigate the effects of distance on gravitational force in different contexts
USEFUL FOR

Students of physics, educators explaining gravitational concepts, and anyone interested in the fundamentals of gravitational theory and its applications.

misogynisticfeminist
Messages
370
Reaction score
0
I was wondering something about gravity and I think someone has posted this before here but i think the thread is gone. Galileo's experiment showed that everything falls onto the Earth at equal acceleration.

So, i messed around and, say if I equate [tex]F=ma[/tex] with [tex]F=\frac {Gm_1m_2}{D^2}[/tex], the masses actually cancel out. Is this the right way to do it? and to explain why the mass of an object doesn't matter when free falling on the Earth's gravitational field?

but also if we take [tex]m_1[/tex] as the mass of the particular object, would [tex]m_2[/tex] be the mass of the Earth? If so, i would get, [tex]m_2 = \frac {g{D^2}}{G}[/tex]. Since the mass of the Earth is constant, then where does D come in here?

Or is my way of doing this totally wrong ? !

Thanks..
 
Last edited:
Physics news on Phys.org
misogynisticfeminist said:
I was wondering something about gravity and I think someone has posted this before here but i think the thread is gone. Galileo's experiment showed that everything falls onto the Earth at equal acceleration.

So, i messed around and, say if I equate [tex]F=ma[/tex] with [tex]F=\frac {Gm_1m_2}{D^2}[/tex], the masses actually cancel out. Is this the right way to do it? and to explain why the mass of an object doesn't matter when free falling on the Earth's gravitational field?

but also if we take [tex]m_1[/tex] as the mass of the particular object, would [tex]m_2[/tex] be the mass of the Earth? If so, i would get, [tex]m_2 = \frac {g{D^2}}{G}[/tex]. Since the mass of the Earth is constant, then where does D come in here?

Or is my way of doing this totally wrong ? !

Thanks..

Nothing you're doing is wrong,just the assumption that D is anything different that Earth's mean radius...or the distance between Earth's center and the object itself...
So,yes,Earth's mass is equal with the product between gravitational acceleration and Earths's mean radius squared devided by Cavensdishs' constant,as long as the object is assumed at the Earths'surface and Earth a spherical body...
 

Similar threads

  • · Replies 10 ·
Replies
10
Views
2K
  • · Replies 5 ·
Replies
5
Views
4K
  • · Replies 30 ·
2
Replies
30
Views
6K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 30 ·
2
Replies
30
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 48 ·
2
Replies
48
Views
7K