迎世博晚会上,彩色气球伴随欢庆的乐曲匀速上升,在此过程中,气

迎世博晚会上,彩色气球伴随欢庆的乐曲匀速上升,在此过程中,气球的
A.动能转化为势能,机械能不变B.动能转化为势能,机械能增大
C.动能不变,势能增大,机械能增大D.动能不变,势能不变,机械能不变

答案

C解析:

相关题目

Peter:   What are you doing for vacation, Steven?Steven:  I’m visiting my a
Peter:   What are you doing for vacation, Steven?Steven:  I’m visiting my aunt in San Francisco. My brother’s staying there. He’s joining a club.Peter:   Oh? When are you going?Steven:  Ne
短文填空。Do you know Sweden?It l (1)in the north of Europe. It is the fo
短文填空。Do you know Sweden?It l (1)in the north of Europe. It is the fourth largest country in Europe with an area of 450,000 square kilometers and a p (2) of about 8.5 million. Over one thir
吸毒严重危害人体健康与社会安宁,是世界的一大公害。摇
吸毒严重危害人体健康与社会安宁,是世界的一大公害。摇头丸是国家严禁的一种毒品,化学式为C9H13N,它由_________种元素组成,每个分子有_____个原子
 We’ll go for a walk if it _________ tomorrow.           A. will no
 We’ll go for a walk if it _________ tomorrow.           A. will not rain         B. isn’t raining       C. doesn’t rain       D. rains     
I came in tired and happy and badly in need_____ a bath. However, my elder broth
I came in tired and happy and badly in need_____ a bath. However, my elder brother insisted there wasn’t much need______ one   A. of; for    B. for; of     C. for; for    D. of; of
选出对下面一段话分析正确的一项                
选出对下面一段话分析正确的一项                 (    )     她需要做手术,可手术费需要七万元啊!这对一个农村家庭来说,是多么沉
 在一恒温体积可变的密闭容器中发生如下反应:A(g)+B(g)2C(g)
 在一恒温体积可变的密闭容器中发生如下反应:A(g)+B(g)2C(g) △H<0。t1时刻达到平衡后,在t2时刻改变某一条件,其反应过程如图。下列说法正确的是
已知在⊿ABC中,∠A=48°,∠C=84°且AB=3cm AC=4cm,则三角形的周
已知在⊿ABC中,∠A=48°,∠C=84°且AB=3cm AC=4cm,则三角形的周长是(   )A.7cmB.10cmC.11cmD.10cm或11cm

最新题目