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Tue February 07, 2012 By: Michelle
What are the similarities and dissimilarities between gravitational force and electrostatic force?
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Gravitational force is the force generated between two masses, such as the Earth and the Moon, an apple and the Earth, or anything else possessing mass in the universe. As a matter of fact, Mars is exerting a gravitational force on you  it extends forever.
The formula for gravitational force is:
Fgrav. = (Gm1m2)/(d2)
where G is the gravitational constant 6.67 x 1011
m1 is one mass in kilograms, m2 is the other mass
d is the separation distance in meters between the two masses.
Electrostatic forces:
Electrostatic force exists between two charged objects. Unlike gravitational force, electrostatic force can be either a force of ATTRACTION or one of REPULSION, depending on the nature of the two charges; like charges repel, opposites attract. But this force also extends forever and its formula is surprisingly similar to the gravity formula:
Felectrostatic = (Cq1q2)/(d2)
where C is Coulomb's constant 8.99 x 109
q1 is one charged object in coulombs of charge, q2 is the other.
d is the separation distance in meters.
But question is , whether the two objects in question will attract or repel. For instance, a proton has a charge of +1.60 x 1019 C. An electron has a charge of 1.60 x 1019 C. They are opposite, so they will attract.
The electrostatic force per unit Q2 exceeds the gravitational force per unit M2 by a factor of almost 1040.
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