Tag: transfer of heat

Which of the following arrangements is correct on the basis of conductivity of materials?

What will be the conductivity of pure silicon crystal at 300 K temperature if  electron cottoer pair at this temperature is $ 1.072 \times 10^{10} /cm^3 $ and $ \mu _n = 1350 cn^2 /V-s and \mu _p = 480 cm^2/ V-s $ ?

 Inorder to have a difference of $25 \,cm$ in their length at all temperatures, the lengths of iron and copper rods at $0^o C$ are $(\alpha _{iron} = 12 \times 10^{-6} {^oC}^{-1}, \alpha _{copper} = 17 \times 10^{-6} {^oC}^{-r})$

The heat capacity of a body depends on 

In a steady state of thermal conduction, temperature of the ends $A$ and $B$ of a $20cm$ long rod are $100^oC$ and $0^oC$, respectively. What will be the temperature of the rod at a distance of $6cm$ from the end $A$ of the rod?

Which of the following is a bad conductor of heat?

A geyser heats water flowing at the rate of 4 litre per minutes from 30 C to 85 C. If the geyser operates on gas burner then the amount of heat used per minute is :

A 2 m long wire of resistance 4 ohm and diameter 0.64 mm is coated with plastic insulation of thickness 0.06 mm, when a current of 5 ampere flows through the wire, find the temperature difference across the insulation in steady state if $k=0.16\times { 10 }^{ -2 }cal/\left( cm{ C }^{ 0 }sec \right) $ 

M g of ice at ${ 0 }^{ \circ  }C$ is mixed with M g of water at ${ 10 }^{ \circ  }C.$ The final temperature is

Name a medium which is a good insulator of heat.