题干

已知长为L的光滑斜面,物体从斜面顶端由静止开始以恒定的加速度下滑,当物体的速度是到达斜面底端速度的一半时,它沿斜面下滑的位移是(   )

A:L2

B:2L2

C:L4

D:(21)L

上一题 下一题 0.0难度 选择题 更新时间:2010-05-22 05:22:16

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C

同类题1

You choose to be a winner!

    The Winners Club is a bank account specially designed for teenagers. It has been made to help you better manage your money. The Winners Club is a transaction account (交易账户) where you receive a key­card so you can get to your money 24/7—that's 24 hours a day,7 days a week!

    It's a club with impressive features forteenagers:

● No account keeping fees!

    You're no millionaire so we don't expect you to pay large fees. In fact, there are no account keeping or transaction fees!

● Excellent interest rates!

    You want your money to grow. The Winners Club has a good rate of interest which gets even better if you make at least two deposits (存款) without taking them out in a month.

● Convenient

    Teenagers are busy — we get that. You may never need to come to a bank at all. With the Winners Club you can choose to use handy tellers and to bank from home using the phone and the Internet...You can have money directly deposited into your Winners Clubaccount. This could be your pocket money or your pay from your part-time job!

● Mega magazine included

    Along with your regular report, you will receive a FREE magazine full of good ideas to make even more of your money. There are also fantastic offers and competitions only for Winners Club members.

    The Winners Club is a great choice for teenagers. And it is so easy to join. Simply fill in an application form. You will have to get permission from your parent or guardian (so we can organize that cool key­card) but it is easy. We can't wait to hear from you. It's the best way to choose to be a winner!

同类题5

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Choose Your One-Day-Tours!

    Tour A - Bath &Stonehenge: including entrance fees to the ancient Roman bathrooms and Stonehenge -£37 until 26 March and £39 thereafter.

    Visit the city with over 2,000 years of history and Bath Abbey, the Royal Crescent and the Costume Museum, Stonehenge is one of the world's most famous prehistoric monuments dating back over 5,000 years.

    Tour B - Oxford & Stratford  including entrance fees to the University St Mary's Church Tower and Anne Hathaway's -£32 until 12 March and £36 thereafter.

    Oxford: Includes a guided tour of England's oldest university city and colleges. Look over the "city of dreaming spires(尖顶)"from St Mary's Church Tower. Stratford: Includes a guided tour exploring much of the Shakespeare wonder.

    Tour C - Windsor Castle &Hampton Court including entrance fees to Hampton Court Palace -£34 until 11 March and £37 thereafter.

    Includes a guided tour of Windsor and Hampton Court, Henry VIII's favorite palace. Free time to visit Windsor Castle (entrance fees not included).With 500 years of history, Hampton Court was once the home of four Kings and one Queen. Now this former royal palace is open to the public as a major tourist attraction. Visit the palace and its various historic gardens, which include the famous maze (迷宫)where it is easy to get lost!

    Tour D -Cambridge including entrance fees to the Tower of Saint Mary the Great -£33 until 18 March and £37 thereafter.

Includes a guided tour of Cambridge, the famous university town, and the gardens of the 18th century.