Bernoullis principle and applications - Question Bank
1. When an object moves through a fluid, the pressure on the leading surface is higher than the pressure on the trailing surface if the fluid is flowing. This pressure difference contributes to:
2. Which of the following conditions must be met for Bernoulli's principle to be accurately applied?
3. The blowing of air across the top of a vertical tube dipped into a liquid causes the liquid to rise and atomize. This is an example of:
4. Consider a fluid flowing through a pipe that expands. According to Bernoulli's principle, as the velocity decreases, the pressure will:
5. In the Bernoulli equation, the term representing the potential energy per unit volume is:
6. The operation of a Pitot tube, used to measure fluid speed, relies on the difference between stagnation pressure and static pressure. This difference is related to:
7. If the pressure in a fluid decreases, and the fluid is flowing horizontally, what must happen to the fluid's kinetic energy?
8. In a Venturi tube, the ratio of the velocity in the wider section to the velocity in the narrower section is equal to the ratio of the cross-sectional area of the narrower section to the cross-sectional area of the wider section. This is due to the:
9. The formula P + (1/2)ρv^2 + ρgh = constant applies to:
10. A common misconception about airplane lift is that it's solely due to the angle of attack pushing air downwards. While this contributes (Newton's third law), the primary mechanism for significant lift is:
11. When a fluid flows through a constriction, its velocity increases. This leads to a decrease in pressure. What is the consequence for the surrounding fluid if the constriction is in a pipe immersed in a larger fluid body?
12. The concept of dynamic lift, as experienced by airplane wings, relies on the difference in air pressure created by the flow of air over a curved surface. This difference in pressure is a direct manifestation of:
13. In a vertical pipe where fluid flows upwards, if the velocity increases, the pressure will:
14. The lift generated by an airplane wing is proportional to the square of the airspeed. If the airspeed is doubled, the lift increases by a factor of:
15. What happens to the potential energy term (ρgh) in Bernoulli's equation when a fluid flows from a higher point to a lower point in a pipe, assuming other factors are constant?
16. A fire hose nozzle is designed to increase the speed of water. This is achieved by:
17. The diagram shows a horizontal pipe with two sections, A and B. Section A has a larger diameter than section B. If a fluid flows from A to B, what is the relationship between pressure P_A and P_B?
18. If a fluid is flowing through a pipe and the pressure decreases, what can be inferred about the velocity of the fluid, assuming horizontal flow and negligible viscosity?
19. Which of the following is NOT a direct application or consequence of Bernoulli's principle?
20. In the case of a horizontal pipe with varying cross-section, if the velocity of the fluid doubles, the kinetic energy per unit volume changes by a factor of:
21. The reduction in pressure as the speed of a fluid increases is most closely related to the conservation of:
22. A sailing boat moves forward because the wind passing over the curved sail:
23. Consider a fluid flowing vertically upwards. How does the pressure change along the flow direction, assuming constant velocity?
24. The pressure difference between the inside and outside of a fast-moving car is:
25. What is the main limitation of Bernoulli's principle when applied to real-world scenarios like water flowing in pipes?
26. In the context of Bernoulli's principle, what is meant by 'steady flow'?
27. When two parallel planes move close to each other, the air between them is forced to move faster. According to Bernoulli's principle, this results in:
28. The 'Bi-plane effect' or the tendency for two parallel planes moving close to each other to be attracted is explained by:
29. Why does a shower curtain tend to move inwards when the shower is running?
30. The operation of a chimney is enhanced by the wind. Wind blowing over the top of the chimney:
31. How does an atomizer work using Bernoulli's principle? A fast-moving stream of air across the top of a vertical tube dipping into the liquid creates:
32. Atomizers, like those used in perfume bottles or spray paint cans, work on the principle of:
33. In the context of Torricelli's Law, what does 'h' represent?
34. Torricelli's Law states that the speed of efflux (v) of a fluid from a small hole at a depth h below the surface is given by:
35. When water flows out of a small hole in a tank, the speed of efflux is related to the height of the water above the hole. This is a direct application of:
36. What is the primary purpose of a Venturi meter?
37. In a Venturi meter, a fluid flows through a pipe with a constriction. The pressure in the constricted part of the Venturi tube is:
38. How does the Magnus effect work for a spinning ball? The spin causes the air velocity on one side to be higher, leading to:
39. The phenomenon of a spinning ball curving in flight (like a curveball in baseball) is explained by:
40. Why does an airplane wing generate lift? The curved upper surface causes air to travel faster than the air flowing under the flatter bottom surface, resulting in:
41. An airplane wing is designed to generate lift. This is primarily explained by:
42. Which of the following is a key assumption for Bernoulli's principle to be strictly applicable?
43. Consider a fluid flowing through a pipe that narrows. According to Bernoulli's principle and the continuity equation, as the area decreases, the fluid velocity increases, and its pressure:
44. For a fluid flowing in a horizontal pipe of varying cross-sectional area, Bernoulli's principle implies that where the speed of the fluid is highest, the pressure will be:
45. What does the term 'ρgh' in Bernoulli's equation represent?
46. In the Bernoulli equation P + (1/2)ρv^2 + ρgh = constant, what does the term (1/2)ρv^2 represent?
47. The equation representing Bernoulli's principle for a horizontal flow of an ideal fluid is given by P + (1/2)ρv^2 = constant. What does 'P' represent in this equation?
48. Bernoulli's principle is a direct consequence of which conservation law?
49. Which fundamental principle of fluid dynamics states that for an inviscid flow, an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluid's potential energy?