57. An electric kettle with resistance 12 Ωis connected to a 110 V (rms), 60 Hz AC power supply. The kettle is used to heat 1.0 L of water. Assuming all electrical energy is converted into heat, approximately how long will it take to raise the water temperature by 1 °C? The specific heat of water is about 4.2
(A) about 2 s
(B) about 4 s
(C) about 6s
(D) about 8 s
(E) about 10 s

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統計: A(0), B(1), C(1), D(1), E(0) #3847833