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 = Fon q/q, and we used this to find the electric field of a point charge. 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. Express your answer in terms of the variables M, r, unit vector r^, and the gravitational constant G. Use the 'unit vector' button to denote unit vectors in your answer.   A spherical planet is discovered with mass M, radius R, and a mass density that varies with radius as ρ=ρ0(1−r/2R), where ρ0 is the density at the center. Determine ρ0 in terms of M and R.     Gauss's law for gravity: integral ∮g →⋅ dA =−4πGMin Find an expression for the gravitational field strength inside the planet at distance r < R.

Principles of Physics: A Calculus-Based Text
5th Edition
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Raymond A. Serway, John W. Jewett
Chapter19: Electric Forces And Electric Fields
Section: Chapter Questions
Problem 64P
icon
Related questions
Question

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 = Fon q/q, and we used this to find the electric field of a point charge. 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.
Express your answer in terms of the variables M, r, unit vector r^, and the gravitational constant G. Use the 'unit vector' button to denote unit vectors in your answer.
 
A spherical planet is discovered with mass M, radius R, and a mass density that varies with radius as ρ=ρ0(1−r/2R), where ρ0 is the density at the center. Determine ρ0 in terms of M and R.
 
 
Gauss's law for gravity: integral ∮g →⋅ dA =−4πGMin
Find an expression for the gravitational field strength inside the planet at distance r < R.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 4 steps with 3 images

Blurred answer
Knowledge Booster
Electric field
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Principles of Physics: A Calculus-Based Text
Principles of Physics: A Calculus-Based Text
Physics
ISBN:
9781133104261
Author:
Raymond A. Serway, John W. Jewett
Publisher:
Cengage Learning
Physics for Scientists and Engineers: Foundations…
Physics for Scientists and Engineers: Foundations…
Physics
ISBN:
9781133939146
Author:
Katz, Debora M.
Publisher:
Cengage Learning