Question

3. (6 pts) Newton's law of gravity and Coulomb's law are both inverse-square laws. Consequently, there should be a "Gauss's law for gravity." The electric field was defined as E" =F" onq/q, and we used this to find the electric field of a point charge. a) Using analogous reasoning, what is the gravitational field g" of a point mass? Write your answer using the unit vector r', but be careful with signs; the gravitational force between two "like masses" is attractive, not repulsive b) What is Gauss's law for gravity, the gravitational equivalent of the Coulomb force? c) Use DG for the gravitational flux, g for the gravitational field, and Min for the enclosed mass

Answer 1

Newton's law at gravity M, and Me F M where ,M2 F = - 92 are the masses of the two point Be absays negative masses and ris That is why it be negative, the distance between them Radially outward contemt Land of Electrme charge Fag- not a win where a ar are the point charges and is in the distance between the charges which in radically ontward Depending on the polarity of charges The Force Cande negative am besitive. were we considered both charges are tre and force is rebelsive. a mmologically we should have an lan like Cour laws in Electrostatics in gravit atron & So Field will de (g) Ra D, M = 5Man alwaysabbade like we do in electrostatics MT 11

2) Gauss lan bon will de dike 6/j.d . - Mim er bich gives abder indeguation et over the surface of a sphere gsds witin gyan? - Min 9 = - 9 Mim 4117? ads since 311 db unse so gods-gdscoso- ads like we do in electrostaties - Ed - 9 months enclosedly → unto the othere where Min is the mass enclosed inside the sphere . e bravitational flux Sards = 86. so In this notation the land will 06 – G8 Min