因为忙于中考复习,小丽已经很长时间没有打开过自己的电脑了,进入潮湿的夏季后,爸爸建议小丽定期给电脑通一会儿电.请你解释这样做的道理.
答:在潮湿的夏季,长时间不用的电脑主机元件会附着上水汽,容易腐蚀损害电子元件,同时容易引起漏电、电线短路等事故.而根据焦耳定律可知,给电脑通电 后,电脑元件会发热,同时也会使附着在电子元件上的水汽温度升高,蒸发加快,使电子元件变得干燥;因此,给电脑通电可以较快的去除电脑主机元件上附着的水 汽,延长电脑使用寿命.
Kate’s brother Danny1some New Year’s resolutions this year. 2 he is going to learn3the guitar. She is going to take the guitar lessons4practice every day. Next he wants to get good5. He is going to study6and he is going to do all his homework7 he watches TV. Finally, he wants to learn8new language. He is going to buy some 9 CDs and practice 10at home every morning.
关于甲、乙、丙、丁四个装置(如下图所示)的说法不正确的是( )
如图,已知正方形ABCD的边长为3,E、F分别是AB、BC边上的点,且∠EDF=45°,将△DAE绕点D逆时针旋转90°,得到△DCM.若AE=1,则FM的长为____.