How can it be inferred that all the bodies in the universe attract each other because of gravitational force?
Unification is basic quest of physics. Great advances in physics often amount to unification of theories. Newton unified terrestial and celestial domains under common law of gravitation.
Gravitational force is force of mutual attraction between any two objects by virtue of their masses. Since this law satisfies maximum areas of physics from vast universe, planetery movement to small objects if not on microscopic level.
You can name it whatever you like and create your own law but chances are it might satisfy on level of earth but may fail on other levels. like Aristotle believed in what he saw and observed on earth but later on his theories came out to be wrong when experiments were conducted.
Coming to second part, why it does not repel?
The gravitational force according to Newton’s law of gravitation is given by:
F=Gm1.m2/r2F=Gm1.m2/r2
where G is gravitation constant, m1 and m2 are masses if two bodies, and r is distance between the two bodies.
Since G is constant The force F is clearly, directly proportional to m1 and m2 & inversely proportional to square of distance between them.
Gravity is always attractive because mass always positive. So they attract always and do not repel
Unification is basic quest of physics. Great advances in physics often amount to unification of theories. Newton unified terrestial and celestial domains under common law of gravitation.
Gravitational force is force of mutual attraction between any two objects by virtue of their masses. Since this law satisfies maximum areas of physics from vast universe, planetery movement to small objects if not on microscopic level.
You can name it whatever you like and create your own law but chances are it might satisfy on level of earth but may fail on other levels. like Aristotle believed in what he saw and observed on earth but later on his theories came out to be wrong when experiments were conducted.
Coming to second part, why it does not repel?
The gravitational force according to Newton’s law of gravitation is given by:
F=Gm1.m2/r2F=Gm1.m2/r2
where G is gravitation constant, m1 and m2 are masses if two bodies, and r is distance between the two bodies.
Since G is constant The force F is clearly, directly proportional to m1 and m2 & inversely proportional to square of distance between them.
Gravity is always attractive because mass always positive. So they attract always and do not repel
