Conduction - I

Which of the following is an example of heat transfer by conduction?

• (a) A fan blowing on your face
  

• (b) A metal spoon heating up in a hot cup of soup
  

• (c) Sunlight warming the earth
  

• (d) Hot air rising from a radiator 

What is thermal resistance in heat conduction?

• (a) A measure of how easily heat flows through a material
  

• (b) A measure of how well a material resists heat flow
  

• (c) The temperature difference between two points
  

• (d) The rate of heat transfer 

What is the unit of thermal conductivity?

• a) W/mK
  

• (b) W/m2K
  

• (c) J/s
  

• (d) K/W 

The temperature distribution in a large thin plate with uniform surface temperature will be (Assume steady-state condition)

• Logarithmic

• Hyperbolic

• Parabolic

• Linear

Unit of thermal diffusivity is

• m²/hr

• m²/hr °C

• kcal/m² hr

• kcal/m. hr °C

Unit of the rate of heat transfer is

• Joule

• Newton

• Watt

• Pascal

Unit of the rate of heat transfer is

• Joule

• Newton

• Pascal

• Watt

Mark the matter with least value of thermal conductivity

• Air

• Water

• Ash

• Window glass

The amount of heat flow through a body by conduction is

• Directly proportional to the surface area of the body

• Directly proportional to the temperature difference on the two faces of the body

• Dependent upon the material of the body

• All of the above

Most metals are good conductor of heat because of

• Transport of energy

• Free electrons and frequent collision of atoms

• Lattice defects

• Capacity to absorb energy