The question and answer are provided, but I am unsure as to why the calculation

Question

The question and answer are provided, but I am unsure as to why the calculation is performed using Celcius and not Kelvins, since the Kelvins answer is wrong.

YOU WERE UNSURE AND INCORRECT 2 um The rate of heat conduction across a piece of material of length L and cross- At where T and T, are the sectional area A is given by temperatures on either side of the material, and k is the thermal conductivity of the material. A woman hiking in the mountains wears a winter coat filled with goose down (thermal conductivity of 0.025 W/m-K), and in the process produces 7.2 x 105 J of body heat per hour. If her body's surface area is roughly 1.5 m2, how thick must her coat be to maintain body temperature if the air temperature is -3°C? 1.2 cm 0.12 mm YOU WERE UNSURE AND CORRECT min IDON'TKNOW YET WHAT YOU NEED TO KNOW The rate of heat conduction across a piece of material of length L and cross-sectional area A is given by L where T, and T, are the temperatures on either side of the material, and k is the thermal At conductivity of the material. A woman hiking in the mountains wears a winter coat filled with goose down (thermal conductivity of 0.025 W/m-K), and in the process produces 7.2 x 103 J of body heat per hour. If her body's surface area is roughly 1.5 m2, her coat must be 7.5 mm thick to maintain body temperature if the air temperature is -3°C The rate of heat conduction through the jacket must equal the rate of heat production by the hiker's body if she is to avoid cooling down. The thickness of the coat is the length L through which the heat conducts At.The rate of the hiker's heat production must be Solving the given equation for L yields: converted to SI units: 7.2 x 105 J/hrx 1 hr /3600 s 200 J/s. Human body temperature is about 37 °C. 1.5/200 0.0075 m 7.5 mm, about a quarter of an inch. Keep in mind that we've assumed here that her entire body is covered, which is unrealistic. Actual jackets are thicker to correct for this.

Explanation / Answer

You should get the same answer in both the cases either using kelvin or Degree celcius. because if we have a question where we are dealing with change in temperature then its same in both the units. Because they are related using linear scale so change will be same/.

T1-T2= 37-(-3)=40

in kelvins 37 degree C =310 K

-3 degree c = 270 K

so the change is stil 40. everything else is same so you should get same answer.

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