Question map
Which one of the following laws of electromagnetism does not give the direction of magnetic field ?
Explanation
The Right-hand thumb rule is used to determine the direction of the magnetic field around a current-carrying conductor [4]. Fleming’s left-hand rule relates the direction of the magnetic field, current, and the resulting force on a conductor [2]. Fleming’s right-hand rule is used to find the direction of induced current when a conductor moves through a magnetic field [3]. In contrast, Faraday’s law of electromagnetic induction states that a changing magnetic field induces an electromotive force (emf) in a conductor, focusing on the magnitude of the induced voltage rather than the spatial direction of the magnetic field itself. While Lenz's law (often associated with Faraday's law) provides the direction of induced current, Faraday's law primarily defines the relationship between flux change and emf magnitude. Therefore, Faraday's law is the only option that does not serve as a rule for determining magnetic field direction.
Sources
- [1] Science , class X (NCERT 2025 ed.) > Chapter 12: Magnetic Effects of Electric Current > 12.2.2 Right-Hand Thumb Rule > p. 200
- [4] Science , class X (NCERT 2025 ed.) > Chapter 12: Magnetic Effects of Electric Current > 12.2.2 Right-Hand Thumb Rule > p. 199
- [2] Science , class X (NCERT 2025 ed.) > Chapter 12: Magnetic Effects of Electric Current > Activity 12.7 > p. 203
- [3] Science , class X (NCERT 2025 ed.) > Chapter 12: Magnetic Effects of Electric Current > EXERCISES > p. 207