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lisabon 2012 [21]
3 years ago
12

Estimate (a) the maximum, and (b) the minimum thermal conductivity values (in W/m-K) for a cermet that contains 83 vol% carbide

particles in a metal matrix. Assume thermal conductivities of 28 and 66 W/m-K for the carbide and metal, respectively.
Physics
1 answer:
velikii [3]3 years ago
7 0

Answer:

  k_max = 31.82 w/mk

  k_min  = 17.70 w/mk

Explanation:

a) the maximum thermal conductivity is given as

k_{max} = k_m*v_m + k_p*v_p

where k_m is thermal conductvitiy of metal

k_p is thermal conductvitiy of carbide

v_m = proportion of metal in the cement = 0.17

v_p = proportion of carbide in the cement = 0.83

            = 66*0.17 + 28*0.83

           k_max = 31.82 w/mk

b) the minimum thermal conductivity is given as

k_{min} = \frac{k_{carbide}* k_{metal}}{k_{metal} v_{carbide} +k_{metal} v_{carbide}}

          = \frac{28+66}{28*0.17 +66*0.83}

       k_min  = 17.70 w/mk

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We have our answer! The car's acceleration is 3 meters per second^{2}.

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