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2011年福建高考理综第22题压轴题是这样的:22.如图甲,在x<0的空间中存在沿y轴负方向的匀强电场和垂直于xOy平面向里的匀强磁场,电场强度大小为E,磁感应强度大小为B。一质量为q(q>0)的粒子从坐标原点O处,以初速度v_0。沿x轴正方向射入,粒子的运动轨迹见图甲,不计粒子的质量。(1)求该粒子运动到y=h时的速度大小v;(2)现只改变入射粒子初速度的大小,发现初速度大小不同的粒子虽然运动轨迹(y-x曲线)不同,但具有相同的空间周期性,如图乙所示;同时,这些粒子在y轴方向上的运动(y-t关系)是简
In the 2011 Fujian College Entrance Examination, the 22nd title question is as follows: 22. As shown in Figure A, in the x<0 space, there exists a uniform electric field along the negative y-axis and a uniform magnetic field perpendicular to the xOy plane. The electric field strength is E, and the magnetic induction intensity is B. A particle whose mass is q (q>0) is from the coordinate origin O at the initial velocity v_0. Injected along the positive direction of the x-axis, the trajectory of the particles is shown in Figure A, excluding the mass of the particles. (1) Find the velocity v of the particle when it moves to y = h; (2) Change the size of the initial velocity of the incident particle, and find that particles with different initial velocity have the same trajectory (yx curve), but they have the same Spatial periodicity, as shown in Figure B; at the same time, the movement of these particles in the y-axis direction (yt relationship) is simply