题干

某起重机将1.2×104N的重物沿竖直方向提起,重物由静止开始向上做变速直线运动,然后做匀速直线运动,已知重物在开始的25秒内上升的高度为36米,在接着的15秒内又匀速上升了12米.如空气的阻力不计,则在匀速运动的过程中,起重机对重物的拉力的功率是____W.如图(甲)所示,小华同学用水平力F拉着木箱在水平方向上运动了距离L,则小华对木箱所做的功为W1.小昕同学沿如图(乙)所示的斜面用同样大小的力F拉着同样的木箱在力的方向上也运动了距离L,小昕对木箱所做的功为W2.则W2____W1(填“>”、“<”或“=”).

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9600,=

同类题2

   Eileen Collins is the first woman ever chosen to be a spaceship pilot. She is also the first woman to command(指挥) a spaceship. Today she has flown more than 5, 000 hours in more than 30 kinds of airplanes.
   Talking about high school, she said, “I began reading all kinds of books about famous women pilots. These women went and flew into dangerous places. Their stories encouraged me.” In 1977 Eileen got a pilot’s license and the following year she graduated from university. She went into space in 1999 at the age of 43. She took with her the hopes and dreams of a nation of young people on the earth.
   Eileen is not only an astronaut but also a wife and the mother of a young daughter. She has short curly hair and friendly brown eyes. She met her husband, Pat, while they were together in the air force(空军).
   When she was named as the First Woman Spaceship Commander in 1998, Eileen smiled and said, “When I was a child, I dreamed about space. It was only a dream that I would be one of the astronauts someday. I hope all children will be encouraged to reach for their dreams, when they see I go into space. I believe dreams do come true!”  
____ How many hours has Eileen flown?
                                                                             
____ When did Eileen go into space?
                                                                             
____ What does Eileen look like?
                                                                             
____ Who did Eileen meet in the air force?
                                                                             
____ Did Eileen believe that her dream would come true?