Water is flowing at the rate of 3km/hr through a circular pipe of 20 cm internal diameter into a circular cistern of diameter 10m and depth 2 m. In how much time will the cistern be filled?

• velocity=3 km/hr =3000 m/s
  internal diameter of circular pipe =20cm =20/2=10cm=radius
  since the radius is in 'cm' we must convert it into 'm' =10/100 =1/10 m
  diameter of cistern(cylindrical shaped)=10m/2 =5m=radius of cistern
  
  now,
  
  time=volume of water in the cistern/volume of water flowing in the pipe
  
  =pie*5*5*2/pie*1/10*1/10*3000(since velocity is the length or height of the circular pipe)
  =50pie/30pie=5/3(since 'pie' and '0' will get cancelled)
  =1.66 seconds=correct value
  
  (OR)
  
  1 hour 40 min=approximate value in kmhr format ...
• 7 years agoHelpfull: Yes(0) No(1)