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प्रश्न
Express 15 m s-1 in km h-1.
उत्तर
1 Km = 1000 m
1 m = `1/1000` Km
1 hour = 60 min = 60 x 60 sec
1 hour = 3600 sec
∴ 15 m/s = `15/1000 xx 3600` km/hr
∴ 15 m/s = 54 km/hr-1
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