Solid objects, such as your desk or a rod of aluminum, can conduct heat. The magnitude of the thermal diffusivity of the material determines how quickly the heat moves through a given amount of material. The equation for thermal diffusivity (a) is given by:
Experiments are conducted to change the thermal conductivity (k) of the material while holding the specific heat (Cp) and the density (ρ) constant. The results are shown graphically.
- a. What are the units of the constant [4.16 × 10-7]? Simplify your answer.
- b. If the specific heat of the material is 780 joules per kilogram kelvin, what is the density of the material?
- c. If the material has a density of 5400 kilograms per cubic meter, what is the specific heat of the material in units of joules per kilogram kelvin?
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