Physics Physics Fluid Dynamics 1 — Questions and Answers
Question 1: What is the SI unit of pressure?
- Pascal (Correct answer)
- Newton
- Joule
- Watt
Correct answer: Pascal
The SI unit of pressure is the Pascal (Pa), equal to one Newton per square meter.
Question 2: What is the buoyant force on a submerged object equal to, according to Archimedes' principle?
- Weight of fluid displaced (Correct answer)
- Weight of the object
- Volume of the object times g
- Mass of the object times g
Correct answer: Weight of fluid displaced
Archimedes' principle states that the buoyant force equals the weight of the fluid displaced by the object.
Question 3: Which property of a fluid describes its resistance to flow?
- Viscosity (Correct answer)
- Density
- Pressure
- Surface tension
Correct answer: Viscosity
Viscosity is the measure of a fluid's resistance to deformation or flow, often described as the 'thickness' of a fluid.
Question 4: In the hydrostatic pressure equation P = P₀ + ρgh, what does g represent?
- Gravitational acceleration (Correct answer)
- Gas constant
- Gravitational potential
- Gauge pressure
Correct answer: Gravitational acceleration
In the hydrostatic pressure equation, g represents the acceleration due to gravity (approximately 9.8 m/s²).
Question 5: The continuity equation in fluid dynamics is based on which conservation law?
- Conservation of mass (Correct answer)
- Conservation of energy
- Conservation of momentum
- Newton's third law
Correct answer: Conservation of mass
The continuity equation states that for an incompressible fluid, the mass flow rate must remain constant, based on conservation of mass.
Question 6: Which of the following is typically treated as an incompressible fluid?
- Water (Correct answer)
- Air
- Steam
- Carbon dioxide
Correct answer: Water
Water is treated as incompressible because its density changes negligibly under normal pressure conditions.
Physics Physics Fluid Dynamics 1
What is the SI unit of pressure?