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Force of gravity

  • Thread starter soulja101
  • Start date
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1. Homework Statement
The force of gravity experienced by a person on earth is 750N. What is the force of gravity on the same person aat each of the following distances, in multiples of the Earth's radius from the centre of earth?


2. Homework Equations

FG=mg

3. The Attempt at a Solution
The answers are A)3 B)10 C)22
750N/9.8N/kg
=76.53
 

Answers and Replies

343
0
If you want to find the force of gravity at different distances use the equation-
F=G* mass1*mass2/distance^2

G=gravitational constant or 6.67*10^-11
masses in kilograms
distance in meters
the final force in newtons
 
D H
Staff Emeritus
Science Advisor
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If you want to find the force of gravity at different distances use the equation-
F=G* mass1*mass2/distance^2
hover:
The universal gravitational constant is not needed to answer this question. (Besides, you didn't give the mass of the Earth.)

Soulja:
Using F=mg is not correct; hover's equation is correct.

You know the force at one Earth radius. Using [tex]F = \frac{G m_1 m_2}{r^2}[/tex], can you determine the relation between the forces if the masses remain constant but the distance is varied?
 
343
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sorry, my bad:blushing:
 
Last edited:
D H
Staff Emeritus
Science Advisor
Insights Author
15,329
681
Nothing to apologize about. You provided the governing equation.
 

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