隔离开关只能用来将电器设备与带电体隔离。
参考答案:错
如图所示,空间有水平向右的匀强电场,竖直平面内有初速度为v的带电微粒沿图中虚线由A到B做直线运动,其能量变化情况为
A.动能减小,重力势能增加,电势能减小
B.动能减小,重力势能增加,电势能增加
C.动能不变,重力势能增加,电势能减小
D.动能增加,重力势能增加,电势能减小
My friend _______ a volleyball, but she ___________a basketball. [ ]
A. doesn't have, have
B. don't have, has
C. doesn't have, has