Starting fromthe equation [tex]\alpha=a/d[/tex] with [tex]\alpha[/tex] in radians and a and d in meters, show that the equation is also valid if [tex]\alpha[/tex] is expressed in arcseconds, a is in AU and d is in parsecs.(adsbygoogle = window.adsbygoogle || []).push({});

Would this be the proper way to show this?

[tex]\alpha=a/d[/tex]

[tex]radians=meters/meters[/tex]

[tex]4.8481*10^{-6} radians / arcsecond = \frac{1.49598*10^{11}m/AU}{3.0857*10^{16}m/pc}[/tex]

Divide the numbers and cancel the m's

[tex]4.8481*10^{-6} radians / arcsecond = 4.8481*10^{-6}AU/pc[/tex]

Cancel the numbers

[tex]radians / arcsecond = AU/pc[/tex]

But radians is still there in the left part of the formula! What did I do wrong?

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# Homework Help: Same equation, different units

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