在负电场中,如何判断电势正负
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一般规定无穷远处电势为零,而沿电场线方向电势逐渐降低,因此负电荷形成的电场中,电势为负,沿电场线逐渐增大
电势正负
关键看
0势点取在哪里
在这里放个静止的正电荷
如果正电荷能
自动跑到0势点,
那这里电势为正。
电势是相对的,只有电势差可以计算且有正负
比较正电荷移动时电场做正负功即可
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