Free Fluid Dynamics MCQs with Answers
363 Fluid Dynamics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Fluid flow is described through speed, pressure and density, including steady flow and the equation of continuity for conserving mass. Bernoulli's equation relates pressure, speed and height, while fluid drag and terminal velocity explain why a falling object eventually moves at constant speed when drag balances its weight.
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Read the Fluid Dynamics notesFree MDCAT chapter notes with key terms363 questions · page 11 of 19
- A. A
- B. B
- C. C
- D. D
Explanation: The equation of stokes law (F = 6πrην) shows that force and velocity are directly proportional to each other for a sphere with constant…
Correct answer: A- A. ↓ and 3 cm³/s
- B. ↑ and 7 cm³/s
- C. ↑ and 11 cm³/s
- D. ↓ and 15 cm³/s
Explanation: applying conservation of volume at the junction (total flow in= total flow out).
Correct answer: ↓ and 15 cm³/s- A. A
- B. B
- C. C
- D. D
Explanation: Where the diameter of a pipe is narrow, pressure will be low, and the water level will decrease. So option A is correct.
Correct answer: A- A. Can't be predicted
- B. h2
- C. h1
- D. h2-h1
Explanation: v=√2g(h1-h2 ; where h1-h2 is the height above the orifice which is directly proportional to v.
Correct answer: h2-h1- A. Average K.E. of its molecules
- B. Average vibrational K.E. of its molecules
- C. Average translational K.E. of its molecules
- D. All of the above
Explanation: According to the kinetic theory of gases, gas pressure arises from collisions of molecules with the walls, which depend on their…
Correct answer: Average translational K.E. of its molecules- A. Increases
- B. Decreases
- C. Remains same
- D. Data is insufficient
Explanation: When the speed is high pressure will be low.
Correct answer: Decreases- A. a1/a2
- B. a2/a1
- C. √a2/√a1
- D. √a1/√a2
Explanation: Using the continuity equation for incompressible flow:A₁v₁ = A₂v₂Rewriting for the velocity ratio:v₁ / v₂ = A₂ / A₁ Thus, the correct…
Correct answer: a2/a1- A. vₐ = vᵦ
- B. Pₐ = Pᵦ
- C. Vₐ > Vᵦ
- D. Both 'a' and 'b'
Explanation: Both velocity and pressure will remain same for the same cross-sectional area of pipe.
Correct answer: Both 'a' and 'b'- A. Linear
- B. Streamline
- C. Tubular
- D. Both A and B
Explanation: Streamline flow is a type of flow in which fluid moves forming a point shape at the front, this makes all the particles in the fluid to…
Correct answer: Streamline- A. Twice as much
- B. 4 times as much
- C. 8 times as much
- D. 16 times as much
Explanation: The pressure required to achieve the same flow rate through two pipes with different diameters is given by the equation:P = 8Lnv/πr^4where…
Correct answer: 16 times as much- A. Drag force
- B. Centripetal force
- C. Centrifugal force
- D. Tabular force
Explanation: In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid…
Correct answer: Drag force- A. The molecules of an incompressible fluid
- B. The molecules of a compressed fluid
- C. Both (A) and (B)
- D. None of the above
Explanation: The cars on the highway behave like the molecules of a compressed fluid as they experience congestion and slower movement due to limited…
Correct answer: The molecules of a compressed fluid- A. Less than water
- B. Nearly equal to water
- C. Greater than water
- D. Three times that of water
Explanation: Density of water is 1000 kg per metre cube, and the density of blood is 1060 kg per metre cube, making them nearly equal.
Correct answer: Nearly equal to water- A. √(v2 + P/ρ)
- B. √(v2 - P/ρ)
- C. √(v2 + 2P/ρ)
- D. √(v2 - 2P/ρ)
Explanation: In a horizontal flow, Bernoulli's equation states that the sum of the pressure energy and kinetic energy per unit volume is constant.
Correct answer: √(v2 + P/ρ)215. Ideal fluid is:
- A. Incompressible
- B. Steady flow
- C. Non - viscous
- D. All of these
Explanation: An ideal fluid is a fluid that is incompressible, steady flow, and non-viscous.
Correct answer: All of these- A. A1V2 = A2V1
- B. A1V1 = A2V2
- C. A1H2 = A2H1
- D. A1H1 = A2H2
Explanation: Option A: A1V2 = A2V1: This is the equation of continuity for fluid flow.
Correct answer: A1V1 = A2V2- A. No internal frictional force
- B. Independent of coordinates
- C. Independent of time
- D. Its density remains constant
- E. Its density remains variable
Explanation: The correct answer is Its density remains constant. This is the characteristic of an incompressible fluid.
Correct answer: Its density remains constant- A. Meter / sec
- B. Meter2 / sec
- C. Meter 3 / sec
- D. Meter 2 / sec2
Explanation: Meter3 / sec is the unit of volume per second. Volume is the amount of space that is enclosed by a three-dimensional figure, and it is…
Correct answer: Meter 3 / sec- A. ρAv
- B. Av
- C. ρv
- D. Av/ρ
Explanation: 𝑀𝑎𝑠𝑠/𝑡𝑖𝑚𝑒 = ρ × 𝑉/𝑇 = ρ × 𝐴 × 𝑑/𝑇 = ρ × 𝐴 × 𝑣Where T is time, V is volume, A is area, v is velocity.Mass flow per second of…
Correct answer: ρAv- A. 3:2
- B. √2 :√3
- C. 4:9
- D. 2:3
Explanation: To determine the correct ratio, we can use the Avogadro's Law, which states that equal volumes of gases at the same temperature and…
Correct answer: 2:3