Two pipes of same length and diameters d and 2d respectively are connected in series. The diameter of an equivalent pipe of same length is________________?

Related Mcqs:

1. The length of a pipe is 1 km and its diameter is 20 cm. If the diameter of an equivalent pipe is 40 cm, then its length is_____________________?

   A. 32 km
   B. 20 km
   C. 8 km
   D. 4 km

2. When time of closure tc = L/v0 (where L is length of pipe and v0 is speed of pressure wavE., the portion of pipe length subjected to maximum head is__________________?

   A. L/4
   B. L/3
   C. L/2
   D. L

3. Two pipe systems are said to be equivalent when_________________?

   A. head loss and discharge are same in two systems
   B. length of pipe and discharge are same in two systems
   C. friction factor and length are same in two systems
   D. length and diameter are same in two systems

4. In series-pipe problems_______________?

   A. the head loss is same through each pipe
   B. the discharge is same through each pipe
   C. a trial solution is not necessary
   D. the discharge through each pipe is added to obtain total discharge

5. A fluid of kinematic viscosity 0.4 cm2/sec flows through a 8 cm diameter pipe. The maximum velocity for laminar flow will be__________________?

   A. less than 1 m/sec
   B. 1 m/sec
   C. 1.5 m/sec
   D. 2 m/sec

6. The horse power transmitted through a pipe is maximum when the ratio of loss of head due to friction and total head supplied is________________?

   A. 1/3
   B. 1/4
   C. 1/2
   D. 2/3

7. For laminar flow in a pipe of circular cross-section, the Darcy’s friction factor f is________________?

   A. directly proportional to Reynolds number and independent of pipe wall roughness
   B. directly proportional to pipe wall roughness and independent of Reynolds number
   C. inversely proportional to Reynolds number and indpendent of pipe wall roughness
   D. inversely proportional to Reynolds number and directly proportional to pipe wall roughness

8. The distance y from pipe boundary, at which the point velocity is equal to average velocity for turbulent flow, is________________?

   A. 0.223 R
   B. 0.423 R
   C. 0.577 R
   D. 0.707 R

   where R is radius of pipe

9. Flow at constant rate through a tapering pipe is________________?

   1. steady flow
   2. uniform flow
   3. unsteady flow
   4. non-uniform flow
   The correct answer is?

   A. (1) and (2)
   B. (1)and(iv)
   C. (2) and (3)
   D. (2) and (4)

10. If a sphere of diameter 1 cm falls in castor oil of kinematic viscosity 10 stokes, with a terminal velocity of 1.5 cm/sec, the coefficient of drag on the sphere is________________?

    A. less than 1
    B. between 1 and 100
    C. 160
    D. 200