Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Toricellis law ? proof ?

  1. Mar 14, 2007 #1
    toricellis law ? proof ??

    1. The problem statement, all variables and given/known data

    Let y(t) and V(t) be the height (in m) and the volume of the water (m^3), respectively, in a resevoir at time t (in s). If the water leaks out through a hole of area a ( in m^2) at the bottom of the resevoir, Toricelli's Law states that dV/dt= -a(squareroot(2gy)) where g is the acceleration due to gravity.

    Suppose that the resevoir is a cylinder of height 5m and radius 50cm and that the hole in the bottom is circular with radius 2.5cm. If we take g=10m/s^2, show that y satisfies dy/dt= -1/200(squareroot(5y))

    2. Relevant equations

    3. The attempt at a solution

    Well i figured the volume of the cylinder is (5/4)pi and area of small circle is 0.00196m^2 i dunno what to do next ?? please help ..
  2. jcsd
  3. Mar 14, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    Express V(t) in terms of y(t).
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook