How many astronomical units (A.U.) make 1 parsec? - Physics

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Long Answer

How many astronomical units (A.U.) make 1 parsec?

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Solution

1 A.U. long arc subtends the angle of 1 s or 1 arc sec at distance of 1 parsec.

Thus, angle 1 sec = `(1 A.U.)/1` parsec

Thus, 1 parsec = `(1 A.U.)/1` arc sec

Thus, 1 parsec = `(630(3600))/11`

= 206182.8

= 2 × 105 A.U.

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Chapter 2: Units and Measurements - Exercises [Page 11]

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NCERT Exemplar Physics Class 11
Chapter 2 Units and Measurements
Exercises | Q 2.43 (a) | Page 11

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