题目

第二节 阅读下面短文，回答文章后面的5个问题。 （E） Most people agree that the direct, assertive(过分自信的) American personality is a virtue, but it sometimes surprises foreigners. In many cultures, respect for older people or those in positions of authority keeps others from expressing their true feelings. But in the US children often argue with their parents, students may disagree with their teachers, and citizens may express opposition to the actions of government. If the soup has a fly in it or the meat is too tough to chew, the diner can complain to the waiter,两个等量同种电荷固定于光滑水平面上，其连线中垂线上有A、B、C三点，如图甲所示，一个电荷量为2C，质量为1 kg的小物块从C点静止释放，其运动的v-t图象如图乙所示，其中B点处为整条图线切线斜率最大的位置（图中标出了该切线）．则下列说法正确的是（ ）A．B点为中垂线上电场强度最大的点，场强E=1 V/mB．由C到A的过程中物块的电势能先减小后变大C．由C点到A点电势逐渐升高D．A、B两点间的电势差=5V