Register to reply

Kepler's Law vs Newton's Amendment

by scottshannon
Tags: amendment, kepler, newton
Share this thread:
Feb6-12, 12:40 PM
P: 2
Hello ..I have a question which I am sure is easy to answer. It has been a long time since I had physics. In a youtube video located here:

She writes a relationship at 4 min which is


Could someone tell me how she gets that? Thank you in advance.....
Phys.Org News Partner Physics news on
Step lightly: All-optical transistor triggered by single photon promises advances in quantum applications
The unifying framework of symmetry reveals properties of a broad range of physical systems
What time is it in the universe?
Doc Al
Feb7-12, 01:41 PM
Doc Al's Avatar
P: 41,471
Quote Quote by scottshannon View Post
She writes a relationship at 4 min which is

That comes from the definition of center of mass. Perhaps her notation is confusing you. She uses 'dm' to represent the distance from the center of mass to the small mass m; d(M) represents the large mass M times the distance between the masses d.

Register to reply

Related Discussions
Kepler's 3rd Law vs. Newton's second for Satellite... Introductory Physics Homework 8
Newton's Variation of Kepler's third law Introductory Physics Homework 1
Kepler and Newton Introductory Physics Homework 6
ACK! Kepler's 3rd + Newton Introductory Physics Homework 8
Amendment to Newton 1 General Physics 5