(2014?响水县二模)家庭用的电热饮水机,有加热和保温两种工作状态.加热前温控开关S1处于闭合状态,闭

2025-04-25 04:20:32
推荐回答(1个)
回答1:

(1)正常加热时的功率:P1=440W;由P=UI.得:饮水机正常工作时电流:I=

P
U
=
440W
220V
=2A;
(2)饮水机保温状态下,只有R1工作,此时功率:P2=40W;由:P=
U2
R
,得:R1的阻值:R1
U2
P2
=
(220V)2
40W
=1210Ω;
(3)饮水机每加热4min,就显示保温状态16min,即每小时加热3次、保温3次;
故:加热时间:t1=3×4min=12min=12×60s=720s;保温时间:t2=3×16min=48min=48×60s=2880s;
饮水机一小时消耗的电能:W=W1+W2=P1t1 +P2t2=440W×720s+40W×2880s=4.32×105J.
答:(1)正常加热时通过饮水机的电流是2A;
(2)保温状态时电阻R1的阻值是1210Ω;
(3)饮水机一小时消耗的电能是4.32×105J.