题干

如图所示是一台单缸四冲程汽油机的____冲程;若飞轮(曲轴)转速为2400r/min.那么,每秒钟燃气推动活塞做功的次数为____次。完全燃烧0.1kg的汽油,放出的热量被质量为100kg、初温为20℃的水完全吸收,可以使水的温度升高____℃.[q汽油=4.62×107 J/kg,c水=4.2×103 J/(kg•℃)]

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做功,20,11

同类题3

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    乡先辈左忠毅公①视学京畿②,一日,风雪严寒,入古寺,庑下一生伏案卧,文方成草;公阅毕,即解貂覆生,为掩户。叩之寺僧,则史公可法③也。及试吏呼名至史公公瞿然注视呈卷即面署第一。

    及左公下厂狱④,史朝夕狱门外;逆阉⑤防伺甚严,虽家仆不得近。久之,闻左公被炮烙⑥,旦夕且死;持五十金,涕泣谋于禁卒,卒感焉。一日,使史更敝衣草屦,背筐,手长镵,为除不洁者,引入,微指左公处。则席地倚墙而坐,面额焦烂不可辨,左膝以下,筋骨尽脱矣。史前跪,抱公膝而呜咽。公辨其声而目不可开,乃奋臂以指眥⑦;目光如炬,怒日:“庸奴,此何地也?而汝来前!国家之事,糜烂至此。老夫已矣,汝复轻身而昧大义,天下事谁可支拄者!不速去,无俟奸人构陷,吾今即扑杀汝!”因摸地上刑械,作投击势。史噤不敢发声,趋而出。

(节选自方苞《左忠毅公逸事》,有改动)

<注释>①左忠毅公:即左光斗,是史可法的老师。因对抗大宦官魏忠贤,下狱,死。②京畿:国都及其附近的地方。③可法:即史可法,抗清被俘不屈而死。④厂狱:明代特务机关东厂所设监狱。⑤逆阉:叛逆的太监,指魏忠贤。⑥炮烙(páo luò):用烧红的铁来炙烧犯人的一种酷刑。⑦眥(zì):眼眶。

同类题4

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    Kay and Charles Giddens sold their home to start a bed and breakfast. Four years later, the couple now dishes out banana pancake breakfasts, cleans toilets, serves homemade cookies to guests in a bed and breakfast surrounded by trees on a mountain known for colorful sunsets.

    “Do I miss the freeways? Do I miss the traffic? Do I miss the trees? No,” says Ms. Giddens. “This is a phenomenon that's fairly widespread. A lot of people are rethinking their lives and figuring out what they want to do.”

    Simple living ranges from cutting down on weeknight activities to sharing housing, living closer to work and commuting(通勤) less, avoiding shopping malls, borrowing books from the library instead of buying them, and taking a cut in pay to work at a more pleasurable job.

    Vicki Robin, a writer, tells us how she deals with the changes in her budget, now far less than what she used to make.

    “You become conscious of where your money is going and how valuable it is,”Ms. Robin says. “You tend not to use thing up. You cook at home rather than eat out. You find your life is not a mess anymore, and you discover your living costs have gone way down.”

    Janet Luhrs, a lawyer, quit her job after giving birth and leaving her daughter with a babysitter for two weeks.“It was not the way I wanted to raise my kids,”she says.“Simplicity is not just about saving money ; it's about me sitting down every night with my kids to a candlelit dinner with classical music.”

    Ms. Luhrs now edits a magazines called Simple Living, which publishes tips on how to buy recycled furniture and shoes, and organize potluck(家常便饭)dinners instead of fancy receptions.

    “Simplicity is about conscious living and creating the life you want. The less stuff you buy, the less money goes out the door, and the less money you have to earn,” Ms. Luhrs explains.