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用电饭锅做饭的过程中,电饭锅很热而连接电饭锅的导线却不热,请你用焦耳定律的有关知识说明产生这一现象的原因。

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答:电饭锅通电时,电饭锅内加热板与连接电饭锅的导线串联,通过的电流和通电时间相同;因电饭锅内加热板的电阻远大于导线的电阻,所以根据焦耳定律Q=I2Rt可知,加热板上电流产生的热量远大于导线上产生的热量,故电饭锅很热而连接电饭锅的导线却不热。

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    Our historic1740 Shenandoah Valley Bed and Breakfast is the perfect place to relax and enjoy the beauty and history of the Valley. Once a haven (避难所) against Indian attacks on the Virginia frontier and later Stonewall Jackson's headquarters during the Valley Campaign (战役) of 1862, our Shenandoah Valley inn(small hotel) now welcomes travelers looking for comfortable bed and board and friendly welcome.

    On Route11,the Old Valley Turnpike, only two miles from Interstate 81 at Woodstock, the inn has a country atmosphere on five private acres along the Shenandoah River. The inn offers 12 guest rooms, a well-equipped meeting room for small managing meetings, many common areas, and lovely grounds to host sendoffs and family gatherings.

    A hearty Inn at Narrow Passage breakfast will get your day off to a great start! If you have special food needs, tell us ahead of time, and we will try to have just what you need.

    “We had a wonderful four-day stay. Quiet and peaceful with the warmth of fireplaces in the room and bar to comfort and relax you. Ed and Ellen make you feel like family. Breakfast was outstanding.” A visitor said.

    After a busy day of hiking or sightseeing, return for a cool drink on the porch in summer or hot, spiced tea by the fire in winter. In the evening, walk down to the river to feed the ducks, or maybe spend a little time fishing.

    We hope you'll be able to visit us soon. We'll do all we can to make your stay a happy one.