$n=1$时,经典图像中电子围绕质子作半径为$a_0$的圆周运动时的总能量。(1) 总能量为:
A: $E=\dfrac{e^2}{8\pi \epsilon_0 a_0}$
B: $E=-\dfrac{e^2}{4\pi \epsilon_0 a_0}$
C: $E=\dfrac{e^2}{4\pi \epsilon_0 a_0}$
D: $E=-\dfrac{e^2}{8\pi \epsilon_0 a_0}$
A: $E=\dfrac{e^2}{8\pi \epsilon_0 a_0}$
B: $E=-\dfrac{e^2}{4\pi \epsilon_0 a_0}$
C: $E=\dfrac{e^2}{4\pi \epsilon_0 a_0}$
D: $E=-\dfrac{e^2}{8\pi \epsilon_0 a_0}$
举一反三
- 两根无限长的均匀带电直线平行,相距$2a$,线电荷密度分别为$+\lambda$和$-\lambda$,试求(1) 每单位长度的带电直线受的作用力 A: $E=0$ B: $E=\dfrac{\lambda^2}{4\pi \epsilon_0 a}$ C: $E=\dfrac{\lambda^2}{2\pi \epsilon_0 a}$ D: $E=\dfrac{\lambda}{4\pi \epsilon_0 a}$
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- 优学院: 曲面(xcosz+ycosx-dfrac {pi} {2}z=dfrac {pi} {2})在点((dfrac {pi} {2},1-dfrac {pi} {2},0))处的切平面方程是( )
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