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【简答题】
在A国留学.妈妈去看她国内带去一个电饭锅,在A国使用时的妈妈发现这个电饭锅好像变“懒”了.煮熟同样一锅饭需要的时间比在国内需要的时间长了许多,为了查明原因,查看了电饭锅铭牌,发现其上标有“220V  550W“,她恍然大悟.原来所在国家(A国)的家庭电路电压为110V. 设电饭锅电阻值不变.请你帮助通过计算判断: (1)该电饭锅的电阻值为多少? (2)该电饭锅正常工作时,将质量为1.5kg温度为23℃的水加热到100℃:至少需要多长时间?[水的比热容为4.2×10 3 J/(kg?℃)] (3)用此电饭锅煮熟同样一锅饭,在A需时间是在中需时间的多少倍? (注:煮熟同样一锅饭需吸收相同的热量)
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