Hi:) A question that I don't understand, and my feeble attempt to answer it. Can anybody give any heads up on this one?(adsbygoogle = window.adsbygoogle || []).push({});

If a physical quantity is dimensionless, it has no units attatched to it. Determine if the following constant is dimensionless and show your reasoning"

[itex]\alpha[/itex]=e^2/[itex]\hbar[/itex]c4(Pi)[itex]\epsilon[/itex][itex]_{}[/itex][itex]_{0}[/itex]

do all these greek scripted letters just stand for constants, and is it dimensionless because there are no S.I units in the equation? im assuming constants like 4 and Pi are not units.

im so confused!!:(

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# Dimensionless physical quantities

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