A cilinder has a radius of 5 cm and on top of the cilinder there is a funnel of 25 cm radius. Every hour, 2 liters of water comes in the cilinder. How do you know how high the water is standing in the cilinder in 5 hours ?

The basis of the cilinder is parallel with the funnel.

1 Answer
Jul 5, 2017


The water will reach a height of 127.33 cm (rounded to 2 decimal places)


Recall that the volume of a cylinder is

#V = pi*r^2*h#

We know the volume (10 litres after 5 hours), the radius ( 5 cm) and #pi# is a constant. So recalling that one litre is equivalent to 1000 cubic centemetres we can fill in the known values

# 10000 = pi* 5^2*h#

#10000 = 3.1415*25*h#

So #h= 10000/(3.1415*25)#

# h= 127.33# cm