Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Magnetic field exists along which of the following?
Moving charges
Stationary charges
Copper
Iron
Moving charges
A magnetic field is produced around any charge that is in motion. Stationary charges produce only an electric field, whereas moving charges give rise to both an electric field and a magnetic field.
A magnetic field is produced around any charge that is in motion. Stationary charges produce only an electric field, whereas moving charges give rise to both an electric field and a magnetic field.
B=4╧А╬╝0тАЛтАЛr2q(v├Чr^)тАЛ тАФ Magnetic field generated by a moving point charge
F=q(E+v├ЧB) тАФ Lorentz force equation acting on a charge
According to Ampere's Law and Oersted's experiment, an electric current (which is a stream of moving charges) creates a surrounding magnetic field. Mathematically, the Biot-Savart Law describes how a moving charge q with velocity v generates a magnetic field B.
Stationary charges (v=0) create an electrostatic field only.
Moving charges (vюАа=0) produce both an electric field and a magnetic field.
Accelerating charges radiate electromagnetic energy in the form of electromagnetic waves.
Copper and Iron do not inherently possess a magnetic field along them unless a current passes through them or they are magnetized.
Operation of electric motors, generators, and transformers through electro-dynamic interaction.
Deflection of electron beams in cathode ray tubes and particle accelerators.
Option B is incorrect because stationary charges only produce an electric field (Coulomb's Law).
Option C (Copper) is a diamagnetic conductor and does not produce a magnetic field by itself unless carrying an electric current.
Option D (Iron) is a ferromagnetic material that can concentrate or retain magnetic lines of force, but it does not intrinsically produce a magnetic field without magnetic domain alignment or electric current flow.
A is correct тАФ A magnetic field is fundamentally produced by the motion of electric charges (electric current).
Remember for exams: A charge at rest produces ONLY an electric field; a charge moving with constant velocity produces BOTH electric and magnetic fields; an accelerated charge produces electric and magnetic fields AND radiates EM waves.