Physics - Online Test

When a fluid is in motion, it must move in such a way that mass is conserved.Consider the steady flow of fluid through a duct (that is, the inlet and outlet flows do not vary with time). The inflow and outflow are one-dimensional, so that the velocity V and density ρ are constant over the area A.

Now we apply the principle of mass conservation. Since there is no flow through the side walls of the duct, what mass comes in overA1 goes out of A2, (the flow is steady so that there is no mass accumulation). Over a short time interval Δt

As volume is same so this equation can be written as 

A1V1=A2V2

This is a statement of the principle of mass conservation for a steady, one-dimensional flow, with one inlet and one outlet. This equation is called the continuity equation for steady one-dimensional flow.

Mean is the average of all numbers. So mean of all the absolute errors will be given by sum of all absolute errorsnumber of errors$\frac{sumofallabsoluteerrors}{numberoferrors}$

Using Kirchhoff’s junction rule at junction A,2 + 5 - 2 - 1 + IAB = 0;IAB = - 4A

The current IAB is directed away from the junction A. Using the junction rule at B 4 + 0.2 - 1.7 - I = 0;

I = 2.5A