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# Physics/Experts

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## Dr. Stephen O. Nelson

U.S.
Available
I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

## Steve Johnson

U.S.
Available
I would be delighted to help with questions up through the first year of college Physics. Particularly Electricity, Electronics and Newtonian Mechanics (motion, acceleration etc.). I decline questions on relativity and Atomic Physics. I also could discuss the Space Shuttle and space flight in general.

#### 2017-04-19 electomagnetism - force that allow ball to be hit/keyboard to be tapped:

Atoms in close proximity feel electromagnetic forces.  When they're really close, the distortion of the electron orbits around the atoms creates electric fields that repel.  The electromagnetic force is

#### 2017-04-18 atoms, touch, and hitting baseballs...:

Hello Jack,    Yes. Our ordinary, everyday definition of touch is looking at it from the macroscopic scale.     Using our everyday, macroscopic, definition of touch, the bat and ball touch. And, let me

That depends on what you consider "hot," the temperature of the water, the construction of the flask, and the amount of time it's open.  There's plenty of math to it, from radiant heat (for vacuum thermos

Hello Prashant,    1. All other things that would affect the efficiency of an insulated vessel being equal, a spherical shape would be most efficient due to a smaller surface area/volume ratio.     2.

#### 2017-04-16 atoms, touch, and hitting baseballs...:

Hi jack,    Well, it's complicated. Our interpretation of the word "touch" has to have (or should have) a definition different from the everyday definition when thinking about individual atoms. Same with

Physics