Answer:
If the starting GPE is doubled than it's KE would also double.

for a solid cylinder:

for a hollow cylinder:

I will look at the case of a hollow cylinder:

That is as far as i get.
Explanation:
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Answer:
1.20⋅1024 atoms
Explanation:
To calculate the number of atoms in two moles of sodium, use dimensional analysis. 2.0 moles Na x 6.022⋅1023g1mol=1.20⋅1024 atoms of Na.