一、选择题1.在图1所示虚线所围的区域内,存在电场强度为E的匀强电场和磁感应强度为B的匀强磁场.已知从左边水平射入的电子,穿过该区域时未发生偏转.设重力可忽略不计,则在此区域中的E和B的方向可能是A.E和B都沿水平方向,并与电子运动的方向相反B.E和B都沿水平方向,并与电子运 First, multiple-choice questions 1. In the area enclosed by the dashed line shown in Figure 1, there is a uniform electric field with an electric field strength of E and a uniform magnetic field with a magnetic induction intensity of B. It is known that electrons injected horizontally from the left pass through the No deflection occurs in the area. If the gravity is negligible, then the direction of E and B in this area may be that AE and B are both in the horizontal direction, and in the opposite direction of the electron movement, BE and B are along the horizontal direction, and Electronic shipment