本题目来源于试卷: Fields D.2 Electromagnetic Fields & Potential，类别为 IB物理学
[单选题]
Two charges separated by a z1dr(jyn w*y+jo3w el 7rt7/ jkg+6 sddistance r are plac tiz:e ls/v/rr thi/7;ed in a medium with permittivity ϵ. The charges are then moved to air so that they hat:e /rh/ z/t;l7irvs ive the same force between them as that in the medium.
What is the distance between the charges in air, knowing that $ϵ$=$ϵ_r$$ϵ_0$?
A. $ϵ_rr$
B. $\frac{r}{ϵ_r}$
C. $\frac{r}{\sqrt{ϵ_r}}$
D. $r\sqrt{ϵ_r}$
参考答案: D
本题详细解析:
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