Excuse me, I ______ I was blocking your way. A. didn’t realize B. don’t realize C. haven’t realized D. wasn’t realizing 答案:A
如图所示,半径R=10 cm的半圆处在匀强电场中,其直径MN与电场方向夹角为60°,将电荷量为+5×10-3 C的点电荷A沿圆弧从M点移到N点,其电势能减少0.5 J,求
(1)电场强度E的大小;
(2)将电荷量为-8×10-3 C的点电荷B沿直线从M点移到N点,电场力做功多少?