Department of Civil Environmental Engineering Name Grade Th

Department of Civil & Environmental Engineering Name: Grade: This quiz has 20 questions and each question has 5 points. 1. The equation of continuity states that: A. Force is continuous throughout the volume of interest. B. Density is constant throughout a control volume. C. Velocity is zero on any non-moving boundary D. The net amount of matter entering a control volume through the surface is equal to the gain in matter within that volume. 2. The flux of momentum per unit volume through a surface i s: flux of momentum per unit volume out of the surface A. Equal to the B. Normal to the surface Equal to the momentum per unit volume times the velocity normal to the surface integrated over the surface The cause of the nonlinear terms in the momentum equation. C. D. Questions from 3 to 5 are based upon the following situation: Consider flow through two round pipes. Pipe A has twice the diameter of pipe B. The mean velocity in each pipe is the same.

Solution

(1) Answer:- (D) The net amount of matter entering a control volume through the surface is equal to the gain in matter with in that volume.

(2) Answer:- (B) Normal to the surface

(3) Answer :- (C ) 4

(4) Answer:- (B) Momentum per unit mass in pipe A is the same as that in B

(5) Answer:- (C ) The mass flow rate in pipe A is less than that in B