Gravitational Fields and Electric fields are analogous in their forms. In the below table is shown the analogous characteristics,
Electric Field 
Gravitational Field 

Origin of Force 
Charge $Q$ 
Mass $m$ 
Force Law 
Coulomb’s Law, 
Newton’s Law of Gravitation, 

$$F_{e}=\frac{Qq}{4\pi \epsilon_{0}r^{2}}$$ 
$F_{g}=G\frac{Mm}{r^{2}}$ 
Definition of Field Strength 
Force acting per unit positive charge. 
Force acting per unit mass. 

$$E_{e}=\frac{Q}{4\pi \epsilon_{0}r^{2}}$$ 
$$g=G\frac{M}{r^{2}}$$ 
Definition of Potential 
Work done in bringing unit positive charge from infinity to the point. $$V=\frac{1}{4\pi \epsilon_{0}}\frac{Q}{r}$$ 
Work done in bringing unit mass from infinity to the point. $$\Phi=G\frac{M}{r}$$ 
Change in Potential energy 
$$E_{p}=q\Delta V$$ 
$$E_{p}=m\Delta \Phi $$ 



**It is very important to realize that although the two fields have
analogous form, the forces between the charged particle is way to stronger than
that between the gravitational attraction between two charged particle due to
their masses. Hence, in all practical electric calculations the gravitational
attraction between them is ignored.
No comments:
Post a Comment