Coupon Accepted Successfully!


Velocity of Efflux

If a liquid is filled in a vessel up to height H and a hole is made at a depth h below the free surface of the liquid as shown in Fig. 9. then velocity of the liquid (v) coming out the container is called velocity of efflux or velocity of flow.
Fig. 9
  • This result was first given by Torricelli, so this is also known as Torricelli’s theorem.
  • The velocity of efflux is independent of the nature of liquid, quantity of liquid in the vessel, and area of orifice.
  • Greater is the distance of the hole from the free surface of liquid, greater will be the velocity of efflux (i.e., 51176.png).
Fig. 10
  • As the vertical velocity of liquid at the orifice is zero and it is at a height (H – h) from the base, the time taken by the liquid to reach the base-level is 51162.png
  • If we make a hole at the middle of the container such that h = h/2. The range (x) will be maximum and it is equal to H (Fig. 11).
Fig. 11
  • If the level of free surface in a container is at height H from the base and there are two holes at depth h and y below the free surface, then the range will be same if the orifice is at a depth h or (H – h) below the free surface.
Fig. 12

Test Your Skills Now!
Take a Quiz now
Reviewer Name