Skip to content

Force On A Current-carrying Conductor

Easyphysics

A straight wire of length m carries a current of A and lies perpendicular to a uniform magnetic field of T; calculate the force acting on this wire.

Select the correct option:

🔒 Solution Hidden from View

Submit your answer to unlock the detailed step-by-step solution.

About This Question

Subject
physics
Chapter
magnetic effects of current and magnetism
Topic
force on a current-carrying conductor
Difficulty
Easy
Year
2025
Tags
force on conductorcurrent elementperpendicular fieldBIL formulamotor principle

Solution

Correct Answer:

N

From NCERT Class 12, Chapter 4 (Moving Charges and Magnetism), a straight conductor of length carrying current in a magnetic field experiences a force , where is the angle between the current direction and the field. This macroscopic force is the collective effect of the Lorentz force on all the moving charges inside the wire. Since the wire is perpendicular to the field, and . Substituting T, A, m: N. The value N halves the answer, as if m. The value N is ten times too large from a decimal-point error. The value N is ten times too small for the same reason. Plausibility check: the units combine as , and a force of about a newton on a short current-carrying wire in a strong field is entirely reasonable.

This easy difficulty physics question is from the chapter magnetic effects of current and magnetism, covering the topic of force on a current-carrying conductor. It appeared in the 2025 exam.

Looking for more practice? Explore all physics questions or browse magnetic effects of current and magnetism questions on RankGuru.