题干

小阳用漏斗和兵乓球做“气体压强与流速的关系”的实验,如图所示.当他用力向上吹气,兵乓球没有被吹起,还是紧贴在漏斗出口.小阳分析:由于气体流速大压强小,所以兵乓球上面的压强大于下面的压强,兵乓球没被吹起.小红不同意他的观点,她认为兵乓球没有被吹起是兵乓球受到重力的作用.请你设计一个实验证明小红的观点是错误的.写出实验步骤和实验现象.

上一题 下一题 0.0难度 选择题 更新时间:2019-07-08 10:10:47

答案(点此获取答案解析)

答:把图中的实验装置倒过来,先用手轻轻托住兵乓球,从漏斗口用力向下吹气,同时松开手,虽然兵乓球受到重力作用,却观察到兵乓球没有被吹落,还是紧贴在漏斗出口,说明兵乓球紧贴在漏斗出口不是因为兵乓球受到重力作用,所以小红的观点是错误的.

同类题4

    Hollywood child star Shirley Temple died on Monday Feb 10th 2014, at home in Woodside, California, from natural causes. "She was surrounded by her family and caregivers," a statement said.
    With her sweet smile and curly blonde hair, she was one of the most popular stars of the 1930s, in hit movies like Bright Eyes and Stand Up and Cheer.
    Her singing, dancing and acting won over fans worldwide. She was given a special Oscar in 1935, when she was just six years old. To this day, she is still the youngest person to receive the award.
    After retiring from films at the age of 21, Temple returned to the spotlight as a politician(政客) and diplomat  (外交官)  .
    Shirley Temple started her film career at three years old. Between 1934 and 1938 she appeared in more than 20 feature films and was the top US movie star at that time.
    As well as being the youngest ever winner of an Oscar (at the age of 6 years and 310 days), Temple was also the youngest person to present one of the statuettes(小雕像). She stood on a chair to give Claudette Colbert the best actress prize for It Happened One Night in 1935.
    At the age of 12 Temple's star burnt out -- her parents stopped her from making movies and sent her to a girls' school. Her final film , A Kiss For Corliss, is available to watch online for free. This is star's final ever moment on the big screen. The actress retired from Hollywood in 1950, but she still appeared occasionally on TV.
    In 2006, she accepted the Life Achievement Award at the 12th Annual Screen Actors Guild Awards.