Introduction

Q. The thickness of the laminar boundary layer on a flat plate at a point A is 2 cm and at a point B, 1 m downstream of A, is 3 cm. What is the distance of A from the leading edge of the plate?

1. 0.50 m
2. 0.80 m
3. 1.00 m
4. 1.25 m

Q. The thickness of the turbulent boundary layer in case of a flat plate parallel to fluid flow is proportional to

1. Square root of the distance from the leading edge
2. (4/5)th power of the distance from the leading edge
3. (1/5)th power of the distance from the leading edge
4. distance from the leading edge

Q. The relative thickness $\left(\delta /x\right)$ of turbulent boundary layer on a flat plate

1. decreases with distance (x)
2. increases with distance (x)
3. remains constant
4. depends on relative roughness

Q. If x is the distance measured from the leading edge of a flat plate, then laminar boundary layer thickness varies as

1. 1/x
2. $x^{4/5}$
3. $x^2$
4. $x^{1/2}$

Q. In fluid flow, the line of constant piezometric head passes through two points which have the same

1. elevation
2. pressure
3. velocity
4. velocity potential

Q. The ratio of the coeffecient of friction drag in laminar boundary layer compared to that in turbulent boundary layer is proportional to

1. $R_L^{1/2}$
2. $R_L^{1/5}$
3. $R_L^{3/10}$
4. $R_L^{-3/10}$

Q. Which one of the following assumptions in deriving the boundary layer equation of flow past a flat plate at zero incidence is not correct ?

1. uniform flow =0
2. Outside boundary layer velocity is $V_0$ throughout
3. The boundary layer thickness $\delta$ is very small compared to distance x
4. Pressure remains constant throughout the flow both within and outside the boundary layer

Q.

Find the ratio of 300 mm to 8 cm

Q. Consider the following statements and pick up the correct ones :

1. The pressure gradient becomes negative when the boundary layer gets separated.

2. Shear stress decreases as the distance from leading edge increases.

1. Only 1 is correct
2. Only 2 is correct
3. Both statements are correct
4. None of statements is correct

Q. Consider the following statements:
Euler's equation of motion
1. can be derived from Navier-Stokes equations.
2. refers to energy balance
3.develops into Bernoulli's equation under appropriate conditions.
4. is applicable to rotational as well as irrotational flows.
Which of these statement are correct?

1. 1, 2, 3, and 4
2. 1 and 2 only
3. 1 and 3 only
4. 3 and 4 only