FM Lecture 1

An ideal fluid is defined as the fluid which

• is compressible

• is incompressible and has negligible surface tension

• is incompressible and non-viscous (inviscid) and has negligible surface tension

• is compressible, viscous has negligible surface tension

Newton’s law of viscosity states that

• shear stress is directly proportional to the velocity

• shear stress is directly proportional to velocity gradient

• shear stress is directly proportional to shear strain

• shear stress is directly proportional to the viscosity

A Newtonian fluid is defined as the fluid which

• is incompressible and non-viscous

• obeys Newton’s law of viscosity

• is highly viscous

• is compressible and non-viscous

Kinematic viscosity is defined as equal to

• dynamic viscosity × density

• dynamic viscosity/density

• dynamic viscosity × pressure

• pressure × density

Dynamic viscosity (μ) has the dimensions as

• MLT^–2

• ML^–1T^–1

• ML^–1T^–2

• M^–1L^–1T^–1

Poise is the unit of

• mass density

• kinematic viscosity

• viscosity

• velocity gradient

The increase of temperature

• increases the viscosity of a liquid

• decreases the viscosity of a liquid

• decreases the viscosity of a gas

• increases the viscosity of a gas

Stoke is the unit of

• surface tension

• viscosity

• kinematic viscosity

• none of the above

The multiplying factor for converting one poise into MKS unit of dynamic viscosity is

• 9.81

• 98.1

• 981

• 0.981

Kinematic viscosity (ν) is equal to

• μ × ρ

• μ/ρ

• ρ/μ

• none of the above