题干

将三个木板1、2、3固定在墙角,木板与墙壁和地面构成了三个不同的三角形,如图所示,其中1与2底边相同,2和3高度相同.现将一个可以视为质点的物块分别从三个木板的顶端由静止释放,并沿斜面下滑到底端,物块与木板之间的动摩擦因数μ均相同.在这三个过程中,下列说法不正确的是(  )

A:沿着1和2下滑到底端时,物块的速率不同,沿着2和3下滑到底端时,物块的速率相同

B:沿着1下滑到底端时,物块的速度最大

C:物块沿若3下滑到底端的过程中,产生的热量是最多的

D:物块沿着1和2下滑到底端的过程中,产生的热鲎是一样多的

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A

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    Here are some English learning tips to help you improve your English.

    Ask yourself weekly: What do I want to learn this week?

    Asking yourself this question every week will help you think about what is most important to you. If you make a plan for each week, you will be surprised to notice how much you have improved your English by the end of the week! This feeling of success will encourage you to learn even more English.

Quickly review before going to bed

    Research has shown that our brains process(加工) information that is fresh in our brains while we sleep. By going over important knowledge before you go to sleep, your brain will work on this information while you sleep!

Speak English aloud.

    Understanding grammar rules does not mean you can speak English well. You need to practice speaking aloud. Speaking by yourself at home and reading the exercises that you are doing will help connect the muscles(肌肉)of your face to the information in your head and improve your pronunciation.

Do five to ten minutes of listening at least four times a week.

    If you decide that you are going to work hard and listen for two hours, maybe you will not do extra listening exercises soon. But if you listen five to ten minutes at least four times a week, you will find it's not so hard to develop the habit of listening to English.

Look for situations to practice your English.

    Learning English in a classroom is important, but using English in real situations will improve your English skills greatly. You can create new situations by using the Internet to listen to news, exchange emails in English with email friends, etc.

____on Learning English

Making a____ plan

※ In this way, you will be surprised to see the ____that you have made in your English by the end of the week.

※ You will be ____to learn even more English.

Reviewing before going to bed

※ Review before going to bed and you still process ____in your mind while sleeping.

Speaking as much as possible

※ Speaking English aloud can ____the muscles of your face with what you have learned and improve your____.

Listening more____

※ It will be ____ for you to develop the habit of listening to English if you listen often rather than once two hours a week.

Practicing English in

real situations

※ By ____ situations and using English, you will improve your English skills greatly.