Q21 of 39 Page 1

Water in canal, 6 m wide and 1.5 m deep, is flowing with a speed of 10 km/hour. How much area will it irrigate in 30 minutes; if 8 cm standing water is needed?

Canal is in the shape of cuboid

Width of canal = 6 m


Height of canal = 1.5 m


Length of canal in 1 hour = 10 Km = 10000 m


Length of canal in 30 min = 5 Km = 5000 m


Volume of canal = L × W × H


= 5000 × 6 × 1.5 m3


Volume of canal = Area of irrigation × height


Area of irrigation


= 562500 m2


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