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Question
An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours to revolve around the earth.
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Solution
Radius of circular orbit = 42250 km
= 42250 × 1000 m
Time taken for one revolution = 24 hours
= 24 × 60 × 60 s
speed = `"distance"/"time"`
= `(2 pi r)/"time"`
= `2 xx 22/7 xx (42250 xx 1000)/(24 xx 60 xx 60)`
= 3073.74 m s−1
= 3.07 km s−1
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