题干

用弹簧测力计拉着木块在水平面上匀速运动,保持弹簧测力计示数稳定,则(  )

A:木块受到的拉力大于摩擦力

B:木块相对弹簧测力计是运动的

C:木块受到的重力和水平面对木块的支持力是一对平衡力

D:在木块上放一钩码后,继续拉动木块匀速运动,弹簧测力计示数变小

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答案(点此获取答案解析)

C

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    If you're dreaming of visiting one of those picture-perfect European towns filled with old-world attractiveness and scenic beauty, here is a look at the most beautiful small towns in Europe.

    Manarola

    Manarola, Italy, is filled with rainbow-colored homes carved right into a wall of stone along the Mediterranean coast. This charming fishing town is famous for its unbelievable wine, and the paintings. There are no cars here, no traffic lights, or traffic noise. You can drive to Manarola, but you'll have to park just outside the town and then take a shuttle bus or walk in on foot.

    Garmisch-Partenkirchen

    Garmisch-Partenkirchen, Germany, is a fascinating mountain town. Once two separate towns, one Roman and the other Teutonic, the 1936 Winter Olympics forced them to combine, though the two sides still have different characters. The town dates back to 15 AD, filled with narrow, cobblestoned streets lined with historic three or four-story buildings painted with regional and religious scenes.

    Marsaxlokk

    The energetic trading port of Marsaxlokk, Malta, was built in 900 BC. Today, this pictures-like town is the main supplier of fish to the island nation that sits in the Mediterranean Sea. It has no modern buildings to ruin its appeal. With such quiet surroundings, including the traditional luzzu's (fishing boats), it's a particularly charming place to visit.

    Portmagee, Ireland

    In a country filled with beautiful towns, Portmagee, is a standout, sitting on the southwest coast of Ireland. This postcard-perfect seaside fishing town has a row of brightly colored buildings along with a rich and colorful history. At The Bridge Bar, you'll find live music many nights of the week along with fantastic food and a fine glass of beer.