This is a power problem which requires the rearranging of a formula. The lamps energy used is 5 N, and the TV’s usage is 116.7 N (rounded from 116.6666repeating). Here my work:
Answer:
option c .
Explanation:
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Answer:
k_max = 31.82 w/mk
k_min = 17.70 w/mk
Explanation:
a) the maximum thermal conductivity is given as

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

= \frac{28+66}{28*0.17 +66*0.83}
k_min = 17.70 w/mk