Answer: 100 suns
Explanation:
We can solve this with the following relation:

Where:
is the diameter of a dime
is the diameter of the Sun
is the distance between the Sun and the pinhole
is the amount of dimes that fit in a distance between the sunball and the pinhole
Finding
:


This is roughly the diameter of the Sun
Now, the distance between the Earth and the Sun is one astronomical unit (1 AU), which is equal to:

So, we have to divide this distance between
in order to find how many suns could it fit in this distance:

Equations of motion (EoM) use EoM <span>v2=u2+2ax</span> to establish velocities at positions shown in blue in drawing from EoM v=u+at for final 1 second of flight time, we can say v=u+g(1) <span><span>2gH−−−−√</span>=<span><span>2g1625H</span>−−−−−−√</span>+g</span><span> then, solve for H [in terms of g]
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