问题
填空题
如图所示,潜水艇能够上浮和下沉是通过改变_______来实现的;潜水艇在上浮过程中,未露出水面之前,所受的浮力将 ______(选填“变大”、“变小”或不变)
答案
自身重,不变
潜水艇通过水仓进水和排水来改变自身重力,从而控制自身的浮沉;因潜水艇的体积不会改变,故潜水艇在水中任意深度中排开水的体积都不变,故所受浮力不变
如图所示,潜水艇能够上浮和下沉是通过改变_______来实现的;潜水艇在上浮过程中,未露出水面之前,所受的浮力将 ______(选填“变大”、“变小”或不变)
自身重,不变
潜水艇通过水仓进水和排水来改变自身重力,从而控制自身的浮沉;因潜水艇的体积不会改变,故潜水艇在水中任意深度中排开水的体积都不变,故所受浮力不变
Teachers need to be aware of the emotional, intellectual, and physical changes that young adults experience. And they also need to give serious (51) to how they can best adapt them selves to such changes. Growing bodies need movement and (52) , but not just in ways that emphasize competition. (53) they are adjusting to their new bodies and a whole host of new intellectual and emotional challenges, teenagers are especially self-conscious and need the (54) that comes from achieving success and knowing that their accomplishments are (55) by others. However, the typical teenage lifestyle is already filled with so much competition that it would be (56) to plan activities in which there are more winners than losers, for example, publishing newsletters with many student-written book reviews, (57) student artwork, and sponsoring book discussion clubs. A variety of small clubs can provide (58) opportunities for leadership, as well as for practice in successful (59) dynamics. Making friends is extremely important to teenagers, and many shy students need the (60) of some kind of organization with a supportive adult barely visible in the background. |
A.care
B.nutrition
C.exercise
D.leisure