What is the magnitude of the magnetic force on a charged particle?

Question

BlackTom AI · Accepted Answer

To determine the magnitude of the magnetic force on a moving charged particle, recall the Lorentz force for a particle with charge q moving with velocity v in a magnetic field B: F = q v × B, whose magnitude is F = |q| v B sin θ, where θ is the angle between v and B.
Option a states F = |q| v B cos θ, which is incorrect because the magnitude depends on sin θ, not cos θ, for the cross product between velocity and magnetic field.
Option b states F = |q| v B sin θ, which matches the correct magnitude expression derived from the cross product; this is the proper formula for the magnetic force magnitude on a moving charge.
Option c states F = I L B sin θ, which resembles the magnetic force on a current-carrying wire, not on a single moving charged particle; it uses current I and length L, making it inapplicable to a single particle scenario.
Option d states F = q v B sin θ. While it has the right sin θ factor, it omits the absolute value on q. Since force magnitude uses the absolute value of the charge to yield a nonnegative magnitude, this form can be ambiguous about sign and is not the standard magnitude expression.
Thus, the option that correctly represents the magnitude is the one with the absolute value of q: F = |q| v B sin θ.

What is the magnitude of the magnetic force on a charged particle?单项选择题

类似问题

A straight wire carries an electric current upwards, to the top of the page. The current is within a uniform magnetic field directed out of the page. What is the direction of the magnetic force on the current?

What is the magnitude of the magnetic force on a current carrying wire?

What happens if a wire carrying current is placed in a magnetic field?

Which of the following pairs of quantities are not always perpendicular?

The force on a charged particle created by its motion in a magnetic field is maximum at what angle between the particle velocity and field?

An electron enters a magnetic field parallel to B. The electron's

A horizontal wire of length 3.0 m carries a current of 6.0 A and is oriented so that the current direction is 50o S of W. The horizontal component of the Earth's magnetic field is due north at this point and has a strength of 0.14 x 10-4 T. What is the size of the force on the wire?

A 2.0 m wire segment carrying a current of 0.60 A oriented parallel to a uniform magnetic field of 0.50 T experiences a force of what magnitude?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单