题干

如图所示,用小刀把铅笔剖开,剥出铅笔芯,将铜线绑在它的一端.照图连接电路,使另一根铜线在铅笔芯上移动,观察灯泡的亮度变化.通过这个实验,我们可以得出的结论是(  )

A:导体越长,它的电阻越大

B:导体越短,它的电阻越大

C:导体横截面积越大,它的电阻越大

D:导体的温度越高,它的电阻越大

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答案(点此获取答案解析)

A

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    Top 4 Amusement Parks in the World

    It's summertime! That means parents have extra time to spend with their children, and what better way to engage in classic fun with family and friends than to visit an amusement park? Take a look at these fun choices — perfect summer trip ideas to fit every budget(预算).

    Cedar Point

    Tickets: $280 for adults, $120 for children

    Praising itself as the roller coaster capital of the world, Cedar Point's 18 coasters will ensure you're riding all day. Reader Alicia Goettemoeller describes the park as a “paradise for excited thrillers” while reader Nick Schuyler says it is “built for grown-up kids.”

    Knoebels

    Tickets: $120 for adults, $10 for children

    This old-fashioned amusement park is a must for your old memory games as well as money saving - admittance and parking are free of charge. Reader Tracy Ginsburg Maier says “a family of 4 can enjoy special offer to eat, swim and ride all day for $100” at Knoebels.

    Kings Island

    Tickets: $340 for adults, $160 for children

    Kings Island is one of the most visited theme parks in the US, with more than 3 million visitors per year. The park is especially known for its family-friendly attractions, such as Snoopy Island. Tickets to the main park also include admission to the nearby water park, Boomerang Bay.

    Dells Water Parks

    Tickets: $140 for adults, $80 for children

    Wisconsin Dells is a water park with dozens of indoor and outdoor water parks to spread around in. One of them, Noah's Ark, is the largest outdoor water park in the US. Many are open year-round and no charge for children under five.