MCQOPTIONS
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MCQOPTIONS
This section includes 12 Mcqs, each offering curated multiple-choice questions to sharpen your Heat Transfer knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
What is the value of the constant C when the condenser is placed horizontally? hHOR=C \([\frac{K^3 p^2 g h_{fg}}{\mu L(T_{sat} – T_L)}]^{0.25}\) |
| A. | 0.942 |
| B. | 0.725 |
| C. | 0.325 |
| D. | 0.027 |
| Answer» C. 0.325 | |
| 2. |
What is the value of the constant C when the condenser is placed vertically? hVER=C \([\frac{K^3 p^2 g h_{fg}}{\mu L(T_{sat} – T_L )}]^{0.25}\) |
| A. | 0.0943 |
| B. | 0.943 |
| C. | 0.725 |
| D. | 0.633 |
| Answer» C. 0.725 | |
| 3. |
What is the relation between the heat transfer coefficient vs its film thickness value at a point x? |
| A. | hx = K/δ |
| B. | havg = \(\frac{8}{3} K/\delta \) |
| C. | havg = δ/K |
| D. | havg = \(\frac{4}{3} \delta/K \) |
| Answer» B. havg = \(\frac{8}{3} K/\delta \) | |
| 4. |
What is the relation between the averaged heat transfer coefficient over the entire condenser length vs its film thickness value at a point x? |
| A. | havg = \(\frac{4}{3} K/\delta \) |
| B. | havg = \(\frac{8}{3} K/\delta \) |
| C. | havg = \(\frac{8}{3} \delta/K \) |
| D. | havg = \(\frac{4}{3} \delta/K \) |
| Answer» B. havg = \(\frac{8}{3} K/\delta \) | |
| 5. |
What is the relation between the averaged heat transfer coefficient over the entire condenser length vs its value at a point x? |
| A. | \(\frac{h_{avg}}{h_x}\) =4 |
| B. | \(\frac{h_{avg}}{h_x} =\frac{2}{3}\) |
| C. | \(\frac{h_{avg}}{h_x} =\frac{4}{3} \) |
| D. | \(\frac{h_{avg}}{h_x} =\frac{3}{4} \) |
| Answer» D. \(\frac{h_{avg}}{h_x} =\frac{3}{4} \) | |
| 6. |
What is the term TL in the Nusselt theory of condensation equation for film thickness?\(\delta = [\frac{4K(T_{sat}-T_L)\mu x}{\rho gh_{fg}}]^{1/4}\) |
| A. | Liquid temperature |
| B. | Gas temperature |
| C. | Wall temperature |
| D. | Bulk temperature |
| Answer» B. Gas temperature | |
| 7. |
What is the expression for the laminar film thickness of the condensate at a distance of x from the top of the condenser? |
| A. | δ=[4K(Tsat – TL)μ x)/(ρ ghfg)]1/2 |
| B. | δ=[4K(Tsat – TL)μ x)/(ρ ghfg)]1/4 |
| C. | δ=[4K(Tsat – TL)μ x)/(ρ ghfg)]1/8 |
| D. | δ=[K(Tsat – TL)μ x)/(ρ ghfg)]1/4 |
| Answer» C. δ=[4K(Tsat – TL)μ x)/(ρ ghfg)]1/8 | |
| 8. |
What is the term delta in the expression for velocity of condensate flow?M°=\(\frac{\rho^2}{\mu}g(\frac{\delta^3}{3})\) |
| A. | Final stable film thickness |
| B. | Film thickness at y |
| C. | Average film thickness |
| D. | Film thickness at x |
| Answer» E. | |
| 9. |
What is the expression for mass flow rate of condensate in a condenser? |
| A. | M°=\(\frac{\rho^2}{\mu}g(\delta y-\frac{y^2}{2})\) |
| B. | M°=\(\frac{\rho^2}{\mu}g(\delta y-\frac{y^3}{2})\) |
| C. | M°=\(\frac{\rho^2}{\mu}g\delta(\frac{y^3}{3})\) |
| D. | M°=\(\frac{\rho^2}{\mu}g(\frac{\delta^3}{3})\) |
| Answer» E. | |
| 10. |
What is the term y in the expression for velocity of condensate flow?U=\(\frac{\rho}{\mu}g(\delta y-\frac{y^2}{2})\) |
| A. | Film thickness |
| B. | Film thickness at y |
| C. | Distance from the wall at x |
| D. | Film thickness at x |
| Answer» E. | |
| 11. |
What is the expression for the flow velocity of the falling film in a vertical condenser? |
| A. | U=\(\frac{\rho}{\mu}g(\delta-\frac{y^2}{2})\) |
| B. | U=\(\rho g(\delta y -\frac{y^2}{2})\) |
| C. | U=\(\frac{\rho}{\mu}g(\delta y-y^2)\) |
| D. | U=\(\frac{\rho}{\mu}g(\delta y-\frac{y^2}{2})\) |
| Answer» E. | |
| 12. |
Which one of the following is not an assumption of condensation heat regime taken to calculate the heat transfer coefficient? |
| A. | Presence of linear temperature profile |
| B. | Absence of high pressure |
| C. | Absence of viscous shear of the vapour |
| D. | Thickness of the film is too small to create a temperature difference |
| Answer» C. Absence of viscous shear of the vapour | |