Conduction - L 2

In this world of style and attitude, we all wear fashionable clothes.

But when go to our school, we all wear the school dress.

The school dress, mainly the shirt and paint usually ironed to look sharp and proper maintained.

The ironed dress look sharp and proper maintained when it ironed, and the unsightly wrinkles disappeared.

To be ironed, when we place the shirt on the iron board, heat is conducted from the iron to the shirt.

The process of iron to removes the unsightly wrinkles transfer heat energy from the iron to the shirt, we say it as conduction.

The conduction is the transfer of heat energy by direct contact.

The transfer of heat occurs in material from a higher temperature to a lower temperature.

And the rate at which heat is transferred over time, we say it as heat current.

Now let's understand the heat transfer by an illustration.

Let's consider two slabs B and C which have the same length L and same cross-section area A and same thermal conductivity k.

Where the thermal conductivity is the ability to conduct heat, we measure it in a unit watts per meter-kelvin.

Now suppose the temperature is 60 C, which is the highest temperature at the left end of slab B.

And the temperature is 30 C, the lowest temperature at the right side of the slab C.

Now let's join both slabs, we say it as a junction, and the temperature at the junction, we say it as junction temperature T.

When we join both slabs a difference in temperature created, which start a heat current flowing from the slab B to slab C.

Let's represent the heat current in slab B and C with symbol and respectively.

Now let's find out the junction temperature.

Now at the junction, the heat leaving from slab B is equal to the heat entering into the slab C.

Lets put the value of and , and calculate the above equation to get the junction temperature T.

Now by solving the equation, we get the junction temperature T as shown above.

Let's put the value of and and solve to get the value of junction temperature T.

The value of junction temperature T is 45 C.

Revision.

The conduction is the transfer of heat energy by direct contact.

The transfer of heat occurs in material from a higher temperature to a lower temperature.

At a junction, the heat leaving from one slab is equal to the heat entering into another slab.

The End