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title: "An electron and a proton are released from rest at different locations in a region containing a uniform electric field \\(\\vec{E}\\). Each particle moves through a distance \\(d\\) under the influence of the electric field alone. Which of the following correctly compares the kinetic energy gained by the electron to that gained by the proton, \\(K_e / K_p\\), and describes their directions of motion relative to \\(\\vec{E}\\)?"
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url: "https://nerd-notes.com/ubq/118059/"
date_modified: "2026-08-04T08:04:56+00:00"
---

# An electron and a proton are released from rest at different locations in a region containing a uniform electric field \(\vec{E}\). Each particle moves through a distance \(d\) under the influence of the electric field alone. Which of the following correctly compares the kinetic energy gained by the electron to that gained by the proton, \(K_e / K_p\), and describes their directions of motion relative to \(\vec{E}\)?

An electron and a proton are released from rest at different locations in a region containing a uniform electric field \(\vec{E}\). Each particle moves through a distance \(d\) under the influence of the electric field alone. Which of the following correctly compares the kinetic energy gained by the electron to that gained by the proton, \(K_e / K_p\), and describes their directions of motion relative to \(\vec{E}\)?

- **A.** Ratio \(K_e / K_p = 1\); electron moves opposite to \(\vec{E}\), proton moves in the direction of \(\vec{E}\)
- **B.** Ratio \(K_e / K_p = 1\); electron moves in the direction of \(\vec{E}\), proton moves opposite to \(\vec{E}\)
- **C.** Ratio \(K_e / K_p = \dfrac{m_p}{m_e}\); electron moves opposite to \(\vec{E}\), proton moves in the direction of \(\vec{E}\)
- **D.** Ratio \(K_e / K_p = \dfrac{m_e}{m_p}\); both particles move in the direction of \(\vec{E}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/118059/*