Q. 244.6( 43 Votes )
When the planet Jupiter is at a distance of 824.7 million kilometres from the Earth, its angular diameter is measured to be 35.72” of arc. Calculate the diameter of Jupiter.
Distance of Jupiter from Earth, D = 824.7 million kilometres
⇒ D = 824.7 × 106 × 103 m
⇒ D = 8.247 × 1011 m
Angular diameter, θ = 35.72”
⇒ θ = 35.72 × 1’/60
Let d be the diameter of Jupiter.
θ = d/D
⇒ d = θD
⇒ d = 1.43 × 108 m
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