---
title: "In a theoretical model of a screened electrostatic interaction, the electric potential in a region of space with spherical symmetry is given by the function \\(V(r) = \\dfrac{C}{r} e^{-r/a}\\), where \\(C\\) and \\(a\\) are positive constants and \\(r\\) is the radial distance from the origin (\\(r > 0\\)). Which of the following expressions represents the radial component of the electric field, \\(E_r(r)\\), as a function of \\(r\\)?"
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url: "https://nerd-notes.com/ubq/121052/"
date_modified: "2026-08-23T04:57:38+00:00"
---

# In a theoretical model of a screened electrostatic interaction, the electric potential in a region of space with spherical symmetry is given by the function \(V(r) = \dfrac{C}{r} e^{-r/a}\), where \(C\) and \(a\) are positive constants and \(r\) is the radial distance from the origin (\(r > 0\)). Which of the following expressions represents the radial component of the electric field, \(E_r(r)\), as a function of \(r\)?

In a theoretical model of a screened electrostatic interaction, the electric potential in a region of space with spherical symmetry is given by the function \(V(r) = \dfrac{C}{r} e^{-r/a}\), where \(C\) and \(a\) are positive constants and \(r\) is the radial distance from the origin (\(r > 0\)). Which of the following expressions represents the radial component of the electric field, \(E_r(r)\), as a function of \(r\)?

- **A.** \(\dfrac{C}{r^2} e^{-r/a}\)
- **B.** \(\dfrac{C}{a r} e^{-r/a}\)
- **C.** \(\dfrac{C}{r^2} \left(1 - \dfrac{r}{a}\right) e^{-r/a}\)
- **D.** \(\dfrac{C}{r^2} \left(1 + \dfrac{r}{a}\right) e^{-r/a}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121052/*