Heat Transfer (Chemical Perspective) – Multiple Choice Questions (MCQs)

1. 145. In Newton's Law of Cooling, what does 'h' represent?

   • A. Thermal conductivity
   • B. Heat transfer coefficient
   • C. Specific heat capacity
   • D. Heat flux

2. 146. What is the unit of heat transfer coefficient (h) in SI units?

   • A. W/(m·K)
   • B. J/(kg·K)
   • C. W/(m²·K)
   • D. W/m²

3. 147. Which law describes the rate of heat transfer by radiation?

   • A. Newton's Law of Cooling
   • B. Fourier's Law of Heat Conduction
   • C. Stefan-Boltzmann Law
   • D. Fick's Law of Diffusion

4. 148. What is the Stefan-Boltzmann constant (σ)?

   • A. A value related to heat capacity
   • B. A fundamental constant in radiation heat transfer
   • C. A measure of thermal conductivity
   • D. A constant in fluid flow equations

5. 149. What is 'blackbody' in radiation heat transfer?

   • A. An ideal surface that absorbs all incident radiation and emits the maximum possible radiation at a given temperature
   • B. A surface that reflects all radiation
   • C. A surface that transmits all radiation
   • D. A surface with zero emissivity

6. 150. What is 'emissivity' (ε)?

   • A. A measure of a material's ability to absorb radiation
   • B. A measure of a material's ability to reflect radiation
   • C. A measure of a material's ability to emit radiation
   • D. A measure of a material's thermal conductivity

7. 151. What is a 'heat exchanger'?

   • A. A device used to transfer heat between two or more fluids at different temperatures
   • B. A device used for chemical reactions
   • C. A device used for fluid separation
   • D. A device used for mixing

8. 152. What is 'radiation shield'?

   • A. A device used to block heat transfer by conduction
   • B. A device used to block heat transfer by convection
   • C. A low-emissivity material placed between two surfaces to reduce radiative heat transfer
   • D. A device used to enhance heat transfer

9. 153. What is 'insulation'?

   • A. Material used to increase heat transfer
   • B. Material used to reduce heat transfer
   • C. Material used to conduct electricity
   • D. Material used for structural support

10. 154. What is the purpose of 'fins' on heat transfer surfaces?

    • A. To decrease the surface area for heat transfer
    • B. To increase the surface area for heat transfer
    • C. To reduce fluid flow
    • D. To increase pressure drop

11. 155. What is 'natural convection'?

    • A. Fluid movement due to density differences arising from temperature variations
    • B. Fluid movement forced by pumps or fans
    • C. Heat transfer through direct contact
    • D. Heat transfer by electromagnetic waves

12. 156. What is 'boiling heat transfer'?

    • A. Heat transfer during a phase change from liquid to vapor
    • B. Heat transfer during a phase change from solid to liquid
    • C. Heat transfer in solids
    • D. Heat transfer in gases