⇒Area of cross-section =π×r21=π×(0.1)2=0.01π sq. m
⇒Speed of water =3 kilometer per hour = 300060=50 meter per minute.
⇒Volume of water that flows in 1 minute from pipe = 50×0.01π=0.5π cu. m
⇒From figure 2, Volume of water that flows in t minutes from pipe = t×0.5π cu. m
⇒Radius (r2) of circular end of cylindrical tank = 102=5 m
⇒Depth (h2) of cylindrical tank =2 m
⇒Let the tank be filled completely in t minutes.
⇒The volume of water filled in tank in t minutes is equal to the volume of water flowed in t minutes from the pipe.
⇒Volume of water that flows in t minutes from pipe = Volume of water in tank
Therefore, t×0.5π=πr22×h2
⇒t×0.5=52×2
⇒t=25×20.5
⇒t=100
Therefore, the cylindrical tank will be filled in 100 minute.