# SSC JE Mechanical Engineering Practice Questions - Fluid Mechanics

Practice Questions for SSC JE Mechanical Engineering exam on Fluid Mechanics. The answers for the questions have been shared below, in case of any doubt or query, feel free to leave a comment in the comment box below.

Q1) Metacentre is the point of intersection of

1. vertical upward force through c.g. of body and center line of body
2. buoyant force and the center line of body
3. mid-point between c.g. and center of buoyancy
4. all of these

Ans: b

Q2) The two important forces for a floating body are

1. buoynacy, gravity
2. buoyancy, pressure
3. buoyancy, inertia
4. inertia, gravity

Ans: a

Q3) The normal stress is same in all directions at a point in a fluid

1. only when the fluid is frictionless
2. only when the fluid is incompressible and has zero viscosity
3. when there is no motion of one fluid layer relative to an adjacent layer
4. irrespedtive of the motion of one fluid layer relative to an adjacent layer

Ans: c

Q4) An idela flow of any fluid must satisfy

1. Pascal law
2. Newton's law of viscosity
3. boundary layer theory
4. continuity equation

Ans: d

Q5) The flow in which the velocity vector is identical in magnitude and direction at every point, for any given instant, is known as

1. one dimensional flow
2. uniform flow
4. turbulent flow

Ans: b

Q6) Two dimensional flow occurs when

1. the direction and magnitude of the velocity at all points are identical
2. the velocity of successive fluid particles, at any point, is the same at successive periods of time
3. the magnitude and direction of the velociy do not change from point to point in the fluid
4. the fluid particles move in plane or parallel planes and the streamline patterns are identical in each plane

Ans: d

Q7) The upper surface of a weir over which water flows is known as

1. crest
2. nappe
3. sill
4. weir top

Ans: c

Q8) The fluid forces considered in the Navier stokes equation are

1. gravity, pressure and viscous
2. gravity, pressure and turbulent
3. pressure, viscous and turbulent
4. gravity, viscous and turbulent

Ans: a

Q9) Specific weight of sea water is more than that of pure water because it contains ______.

1. dissolved air
2. dissolved salt
3. suspended matter
4. all options are correct

Ans: d

Q10) For very high discharge a low pressure such as for flood control and irrigation applications, which of the following types of pumps is preferred?

1. Centrifugal
2. Axial flow
3. Reciprocating
4. Mixed flow

Ans: b

Q11) The hydraulic radius in the case of an open channel with great width is equal to

1. depth of channel
2. 1/2 x depth of channel
3. 1/3 x depth of channel
4. 1/4 x depth of channel

Ans: a

Q12) When a liquid rotates at constant angular velocity about a vertical axis as a rigid body, the pressure

1. varies as the square of the radial distance
2. decreases as the square of the radial distance
3. increases linearly as the radial distance
4. varies inversely as the elevation along any vertical line

Ans: a

Q13) To replace a pipe of diameter D by 'n' parallel pipes of diameter d, the formula used is

Ans: d

Q14) Discharge through a totally submerged orifice is directly proportional to

1. the difference in elevation of water surface
2. the square root of the difference in elevation of water surface
3. the square root of the area of the opening
4. reciprocal of the area of the opening

Ans: b

Q15) The shear stress in a fluid flowing in a round pipe

1. is constant over the cross section
2. is zero at the wall and increases linearly to the center
3. is zero at the center and varies linearly with radius
4. varies parabolically across the section

Ans: c