摩擦力做功的特点

"all work and no play makes Jack a dull boy" 这句谚语的出处是是么? 在一个容积为500ml的密闭容器中,充入5mol的H2和2molCO.在一定条件下,发生如下反应：2H2（g）+CO（g）---（为可逆号,且条件是催化剂）CH3OH（g）,经过5s后达到平衡状态.若此时CH3OH蒸气的浓度为2mol/ CO+2H2=CH3OH 反应条件是什么? All work no play makes Jack a dull boy 这句话有没有问题All work no play makes Jack a dull boy这一句话是 make sb do sth 使某人怎么样.上面makes后面怎么没有动词呀.换成这样行不行：All work no play makes Jack become a They live a___(和平）life in a small town. When do you finish your classes?______ 4:30 P.M..Every day I can play computer games____ one hour. When are your classes? When does your brother ( )classes?A:start B:starts C:to start D:starting 为什么电力系统中的谐波一般为奇次的 怎样消除奇次谐波? 容器的容积为5L,压强为P,用容积为0.1L的抽气筒向外抽气,在温度不变的条件下,（1）抽10次后容器内气体的压强是多大?（2）抽多少次压强减小到原来压强的一半? 为什么三相交流电电能质量测试中,奇次谐波的含量高于偶次谐波含量? 如图所示,容器B的容积VB=5L,内盛有压强P1=1.0*10^5Pa的空气,装置A是一个打气筒,其下端K1,K2为两个单向阀门，K1进气，K2排气，活塞的面积为15cm^,质量不计。用一根体积可不计，用一根体积可不计 为什么奇谐函数的傅氏级数偶次谐波为0? 为什么用潮湿的毛巾吸水性比干燥的毛巾吸水性好? 请问Warte auf mich 好像是德语. 英语翻译In the past,children did not have computer games,TVs,or many books to read,so they often created1 their own games.They spent a lot of time in their classrooms or doing chores at home.A lot of them thought outdoor games were the most inter 英语翻译You change the sound of my name A moment of truth that I saw in youΓ face It hurts inside,a moment this vile That you brought alive All the roads lead back to you Give me something to return to In your heart I fear nothing but to leave h Do you know ____they live in the same city?A what B if C where D that as often as I know,they live in the same neighbourhood什么意思谢谢广大网友了, they live in a place that many people from Singapore do not know exists.that 引导什么从句?know --exists ,exist 只有动词的词性,这个为什么在know后面? They know they have tofind a warm place to live in f__the winter 1、淀粉、纤维素、糖原都是由简单的糖类聚合而成的.为什么不对?2、从生物系统的结构层次看,细菌除了细胞,还有什么层次? do you like to travel ＿ ＿ or ＿ sea?你喜欢在陆上还是海上旅行?说明为什么哦 厌氧生物处理反应器启动时的注意事项有哪些? 可不可以说电流一定时,电压与电阻成正比呢 宿舍楼每层36个喷淋,一共5层,300个洗澡,假设同时洗澡的话,那用25吨每小时的水泵打热水够用吗?我的水泵只打热水,冷水有自然的压力进去,洗澡的话冷水至少也要参点进去的吧 在功率放大电路中的旁路电容,在那里是起到什么作用的啊?电流是怎样流过旁路电容的?在甲类功率放大电路中的旁路电容,在那里是起到什么作用的啊?电流是怎样流过电容的?不用可不可以? OOCL公司 WE TAKE IT PERSONALLY什么意思呀董建华的东方海外OOCL公司的口号 WE TAKE IT PERSONALLY什么意思呀 "don't take it personally" 普通话是什么? in either case i wouldn't take it personally.这句话啥意思还有一句话；There no reason you couldn't pop in to say hi and to make yourself known.pop怎么理解 control freak和take personally control take personally