# B Presentation of mass as a physical quantity

Tags:
1. Feb 2, 2019

I have started hosting a "scence open mic" and the first one last month was very successful so I'm doing it again. We had about 30 people show up and 5 presenters including myself giving up to an 18 minute talk on anything science. It was a great experience and I encourage others to try it in their town.

Now to my question. For the next open mic I am going to give a presentation on mass focusing on inertial and gravitational mass and their relationship along with Roland Eotvos' pendulum experiment showing their equivalence, followed by Einstein's Equivalence Principle epiphany. If I have time I will talk about the mystery of the absolute nature of rotational forces and acceleration.

My question is this. Can one conclude that Eotvos' work which Einstein cited in 1919, lead to Einstein's epiphany of the Equivalence Principle, or were there some intermediate steps involved? The wiki entry that I am referring to is this:

"The weak equivalence principle plays a prominent role in relativity theory and the Eötvös experiment was cited by Albert Einstein in his 1916 paper The Foundation of the General Theory of Relativity."

I find the work of Eotvos fascinating and was happy to find this relationship with Einstein.

In addition, can anyone recommend any other aspects of mass that would be worth talking about? I'm very excited about this presentation and want to make it a good one. Thanks for any suggestions.

2. Feb 7, 2019

### jambaugh

You might expand upon generalizations and analogs of mass as with angular momentum in rotational motion and (self) induction in electrical currents.

3. Feb 7, 2019

### Staff: Mentor

It would help if you would link to it instead of just quoting it.

4. Feb 9, 2019

### sweet springs

Equivalence of inertial mass and gravitational mass is the saying based on the traditional way of thinking based on Newoton's two formula, F=ma and
$$F=-G\frac{Mm}{r^2}$$. I would say forget about mass and watch acceleration a. The point is everything get the same acceleration under gravity force, how much or less (except zero) mass it has, which is property of space-time. I say here "gravitationa mass" in the sense receipent of gravitational force genertated by the others, not power source of gravitational force acting the others.

Last edited: Feb 9, 2019
5. Feb 13, 2019 at 5:45 PM

### nitsuj

the concept of centre of momentum help me better "understand" mass.