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Question
During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, 3 × 108m s−1.
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Solution
Time taken by the signal to reach the ground station from the spaceship.
= 5 min
= 5 × 60
= 300 s
Speed of the signal = 3 × 108 m/s
`"Speed"="Distance travelled"/"Time taken"`
∴ Distance travelled = Speed × Time taken
= 3 × 108 × 300
= 9 × 1010 m
Hence, the distance of the spaceship from the ground station is 9 × 1010 m.
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