题目内容
表一是某电热水壶的铭牌；表二是小红探究该电热水壶效率所记录的数据。
表一： 表二：
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求：（1）电热水壶的电阻。
（2）当电热水壶实际工作电压为110V时，它的实际功率。
（3）电热水壶的效率。[c水=4.2×103J/（kg·℃）]
（1）
····································································· 1分
···························································· 1分
································································· 1分
（2）解法一：
··························································· 1分
······················································ 1分
··································································· 1分
解法二：
3分
（3）
······························································ 1分
··········································································· 1 分
阅读快车系列答案
表一：
| 产品型号 | SWF12P1A-150 |
| 额定电压U/V | 220 |
| 电源频率f/Hz | 50 |
| 额定功率P/W | 1200 |
| 容量V/L | 1.2 |
| 电源电压U电/V | 220 |
| 壶内水的质量m/kg | 1 |
| 水的初温t1/℃ | 33 |
| 水的沸点t2/℃ | 98 |
| 水从初温加热至刚沸腾的时间t/s | 250 |
（1）电热水壶的电阻．
（2）当电热水壶实际工作电压为110V时，它的实际功率．
（3）电热水壶的效率．[c水=4.2×103J/]．