19. 某一線徑1.6m/m之電線1Km長之電阻值為8.931Ω,熱阻抗為415。若周遭溫度為20℃,當此電線通過35安培時,其心線溫度(℃)為何?
(A) 46
(B) 51
(C) 66
(D) 71
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統計: A(28), B(55), C(95), D(40), E(0) #2861682
統計: A(28), B(55), C(95), D(40), E(0) #2861682
詳解 (共 1 筆)
#5381568
Q=I2R = 352× 8.931×10-5Ω = 10940.475 ×10-5 =0.10940
(T1-T2)
=0.10940×415
T1 - 20 = 45.401
T1 =65.401
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