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FAQ
Frequently Asked Questions
There are four files you can search to see if there is an earlier answer to your question. They are, in chronological order, the most recent first:
http://www.askthephysicist.com/ask_phys_q&a.html
http://www.askthephysicist.com/ask_phys_q&a_old2.html
http://www.askthephysicist.com/ask_phys_q&a_old.html
http://www.askthephysicist.com/ask_phys_q&a_older.html
Below are some FAQs to which I will add periodically.
How
much force is needed to make something have a certain speed. (First,
note that this question has no answer. For the details see the link.)
Can
you give me some idea about the size of an atom?
Why
is acceleration due to gravity independent of mass?
What
was there before the big bang? Where did the big bang come from?
I will answer
that right here after many times giving this answer: nobody knows.
Questions
about air friction (drag, air resistance) and terminal velocity.
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Why
can no object with mass go faster than the speed of light or even as
fast as the speed of light.
If
atoms are mostly empty space, why does stuff seem so solid?
What
is gravity? Does gravity bend light? What is general relativity? What is
the equivalence principle?
Questions
involving acceleration, force, linear momentum, and Newton's second law
in special relativity.
Can
you communicate faster than the speed of light by pushing, pulling, or
rotating a very long rod or string?
Why
is E=mc2 apparently not true for photons which have
zero mass but nonzero energy?
What
happens if you drop something into a hole through the middle of the
earth?
What
are the meaning of the words heat, temperature, hot, cold?
Why
is the speed of light constant to all observers?
Questions
involving gravitons.
If
you shine a flashlight forward in a fast-moving spacecraft, why does the
light not go faster than the speed of light (and similar questions like
this).
Who
wins a race of between a light and heavy car down a ramp? There are
several answers which this link will link to.