A.Thermal conductivity of a medium may be defined as (a) amount of heat flow through 1 m2 area for..

A.Thermal conductivity of a medium may be defined as (a) amount of heat flow through 1 m2 area for temperature gradient of 1 K (b) rate of heat transfer through 1 m2 area for temperature gradient of 1 °C ( c) amount of heat flow through 1 m2 area for temperature gradient of 1 °C/m(d) rate of heat flow through 1 m2 area for temperature gradient of 1 °C/m B. Heat is conducted through a pure metal due to (a) vibration of lattice structure (b) flow of free electrons (c) density difference (d) none of the above C. The value of heat transfer coefficient depends on (a) velocity of fluid
A.Thermal conductivity of a medium may be defined as (a) amount of heat flow through 1 m2 area for temperature gradient of 1 K (b) rate of heat transfer through 1 m2 area for temperature gradient of 1 °C ( c) amount of heat flow through 1 m2 area for temperature gradient of 1 °C/m(d) rate of heat flow through 1 m2 area for temperature gradient of 1 °C/m B. Heat is conducted through a pure metal due to (a) vibration of lattice structure (b) flow of free electrons (c) density difference (d) none of the above C. The value of heat transfer coefficient depends on (a) velocity of fluid and temperature difference (b) thermal conductivity and dynamic viscosity ( c) geometry of surface and its ambient (d) all of the above D. A gray body has one of the following properties: (a) It reflects all of the energy falling on it. (b) It transmits all of the energy falling on it. ( c) It has constant emissivity. (d) It absorbs all of the energy falling on it. E. 0000Which one of the following heat exchanger is most efficient for a given surface area and temperature difference? (a) Parallel flow heat exchanger (b) Counter flow heat exchanger (c) Cross flow heat exchanger (d) Shell and tube type heat exchanger