How does a car radiator help energy transfer ??

Question

also is it the same for the thingy at the back of a freezer ???

Answer 1

lilman...is correct.

Both are radiators, even though they're not both called that. The physics, since this is the physics category, is in the heat transfer equation dQ/dt = kA delT/L; where dQ/dt is the rate of heat (Q) transfer over time (t), k is an object specific constant (like a radiator), A is the area of contact where the heat is transferred, delT = T1 - T0 which is the difference in temperature across the object, and L is the thickness across which the heat travels between the two temperatures.

Three things about radiators (and the thingy in back) is that they are shaped to give a high value for A and a low value for L. This is why radiators, for example, are wide and tall (for A) and thin (for L). And the thingy in back typically has vanes all through it, like rows of metal leaves; these also increase the A. Also the coefficient k is also high because of the materials (high heat conducting metals) used to transfer the heat.

And from the rate of heat transfer equation, you can see the bigger A and k, and smaller L makes dQ/dt a higher rate. Thus, the heat of the engine and reefer are transferred at high rates and exhausted to the outside, cooler air as the hot fluids CFC and water are pumped through the radiator and thingy.

Answer 2

it is some sort the same. Only difference is the system. car pumps water to the hot parts of the engine and water absorbs da heat(energy) and water is pumped out and cooled. The same process is done repeatedly.

In the case of the freezer, It uses CFC, it is pumped to the top region of the freezer and CFC absorbs heat and releases it at the back of the freezer.