---
title: "A particle with charge \\(-4.0\\text{ }\\mu\\text{C}\\) moves with an instantaneous velocity \\(\\vec{v} = (5.0 \\times 10^3\\text{ m/s})\\hat{i}\\) through a region of uniform magnetic field \\(\\vec{B} = (0.30\\text{ T})\\hat{j} + (0.40\\text{ T})\\hat{k}\\). What is the instantaneous magnetic force vector \\(\\vec{F}_B\\) exerted on the particle?"
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url: "https://nerd-notes.com/ubq/121199/"
date_modified: "2026-08-23T04:58:49+00:00"
---

# A particle with charge \(-4.0\text{ }\mu\text{C}\) moves with an instantaneous velocity \(\vec{v} = (5.0 \times 10^3\text{ m/s})\hat{i}\) through a region of uniform magnetic field \(\vec{B} = (0.30\text{ T})\hat{j} + (0.40\text{ T})\hat{k}\). What is the instantaneous magnetic force vector \(\vec{F}_B\) exerted on the particle?

A particle with charge \(-4.0\text{ }\mu\text{C}\) moves with an instantaneous velocity \(\vec{v} = (5.0 \times 10^3\text{ m/s})\hat{i}\) through a region of uniform magnetic field \(\vec{B} = (0.30\text{ T})\hat{j} + (0.40\text{ T})\hat{k}\). What is the instantaneous magnetic force vector \(\vec{F}_B\) exerted on the particle?

- **A.** \((-8.0\hat{j} - 6.0\hat{k}) \times 10^{-3}\text{ N}\)
- **B.** \((-8.0\hat{j} + 6.0\hat{k}) \times 10^{-3}\text{ N}\)
- **C.** \((+8.0\hat{j} - 6.0\hat{k}) \times 10^{-3}\text{ N}\)
- **D.** \((+8.0\hat{j} + 6.0\hat{k}) \times 10^{-3}\text{ N}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/121199/*