Multiple choice

Water flows at the rate of 7 m/min through a pipe with circular cross section of radius 2 cm. The volume of water which flows out it in 10 minute in litres is

  1. 44 lit

  2. 88 lit

  3. 66 lit

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Volume = cross-section area * flow rate * time. Area = pi * r^2 = pi * (2 cm)^2 = 4 * pi cm^2. Flow rate = 7 m/min = 700 cm/min. Time = 10 min. Volume = 4 * pi * 700 * 10 = 28,000 * pi cm^3. Since 1000 cm^3 = 1 liter, Volume = 28 * pi liters = 28 * 3.14 = 87.92 liters, which is approx 88 liters.

AI explanation

The pipe's radius is 2 cm, and the water flows at 7 m/min, which equals 700 cm/min, so the volume of water flowing in one minute is pi * 2^2 * 700 = 2800*pi cubic cm. In 10 minutes, the total volume is 10 * 2800 * (22/7) = 88000 cubic cm. Since 1000 cubic cm equals one liter, dividing by 1000 gives the final volume of 88 liters.

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