Class 11 Physics - Chapter Unit and measurment NCERT Solutions | When the planet Jupiter is at a distance
When the planet Jupiter is at a distance of 824.7 million kilometers from the Earth, its angular diameter is measured to be 35.72" of arc. Calculate the diameter of Jupiter.
Distance of Jupiter from the Earth, D = 824.7 × 106 km = 824.7 × 109 m
Angular diameter = 35.72" = 35.72 x 4.874 x 10-6 rad
Diameter of Jupiter = d
Using the relation,
θ = d / D
d = θD
= 824.7 x 109 x 35.72 x 4.874 x 10-6
= 143520.76 x 103
= 1.435 x 105
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