Physics gravitational questioon

AI Thread Summary
To find the point where the gravitational force from Earth is twice that from the Moon, apply Newton's law of universal gravitation. The gravitational force from Earth at a distance Re from its center can be expressed, as can the force from the Moon at a distance Rm. The distance between the centers of the Earth and Moon is 3.84 x 10^8 meters. By setting the gravitational force from Earth equal to twice that from the Moon, the relationship can be solved for the specific distances. This approach allows for determining the required point along the line connecting the two celestial bodies.
crystal5428
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I need a help.

Find the point where the gravitational force from the Earth is 2 times of that from moon.
 
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crystal5428 said:
I need a help.

Find the point where the gravitational force from the Earth is 2 times of that from moon.
What is the force of gravity at a point Re from the centre of the earth? What is the force of gravity at a point Rm from the centre of the moon? What is Rm at a point on a line between the centres of the Earth and moon that is Re from the centre of the earth?

AM
 
only the mass of earth, mass of moon and radius of moon and Earth is given.
mass of earth=5.98*10(to the power of 24)
mass of moon=7.35*10(to the power of 22)
radius of Earth and moon=3.84*10(to the power of 8)
 
crystal5428 said:
only the mass of earth, mass of moon and radius of moon and Earth is given.
mass of earth=5.98*10(to the power of 24)
mass of moon=7.35*10(to the power of 22)
radius of Earth and moon=3.84*10(to the power of 8)
The distance between the centres of the Earth and moon is 3.84 x 10^8 m or 3.84 x 10^5 km.

Just use Newton's law of universal gravitation to express the force of gravity from the Earth at a distance R from the centre of the Earth (R>radius of the earth). Same for the moon. Then set the force of gravity of the Earth equal to twice the force of gravity of the moon.

AM
 

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