题干

飞机以150m/s的水平速度匀速飞行,某时刻让A球落下,相隔1s又让B球落下,不计空气阻力,在以后的运动中,关于A球和B球的相对位置关系,正确的是(   )

A:A球在B球的前下方

B:飞机上的人看A,B两球均做自由落体运动

C:站在地面上的人看A,B两球均做平抛运动

D:A球在B球的正下方,距离随时间的增加而增加

上一题 下一题 0.0难度 选择题 更新时间:2017-10-09 03:55:02

答案(点此获取答案解析)

B,C,D

同类题2

阅读下面5个人喜欢的电视节目的叙述,并从5个相关信息里中选出合适的信息。(5分)

____ . Although Rob leads a quiet life in a small village, that doesn’t stop him from wanting to find out about the latest scientific development.
____ . Bella enjoys eating out but can’t afford to spend very much at the moment as she is saving for a holiday. She has never learnt how to cook, so now might be quite a good time to find out!
____ . Dan is interested in taking wildlife photographs and enjoys the kind of program
which gives him a chance to see a professional photographer at work.
____ . Gina is a music teacher. Although she prefers classical music, she likes to know the kind of music that interests the teenagers she teaches.  
____ . Bon’s wife is in hospital. He wants to find a program suitable for his three-year-old son while he does the housework and cooks a meal.  


A. TV1 7:20 pm  Find out more about Australia’s animal life. This film was made last year by one of Australia’s best- known photographers, Dougie Bond. He spent over 200 hours filming the birds, animals and fish in Australian bushes.
B. TV3 9:00 pm  The science program is about the latest technology and medicine. This week, cars that run on sunlight and story of one baby’s fight to live.
C. TV3 7:40 pm  This is the program that tells you all about what’s happening on the music scene and tomorrow’s young artists.
D. TV1 5:15 pm  Busy parents? Bored children? Do you want something educational to entertain your children while you do something else? This popular program is for the under-fives. More music, fun, songs and games with Carla and Larry.
E. TV2 8:45 pm  If you have always wanted to cook, now’s your chance to learn. In the studio,there are two chefs who will teach you some simple recipes step by step.