What key consequence arises from Maxwell’s equations regarding the nature of electromagnetic waves?
Show answer & explanation
Correct answer: C
Explanation
Solution: The correct answer is A changing electric field produces a magnetic field and vice versa, enabling self-sustaining wave propagation in a vacuum.
Explanation:
☛ James Clerk Maxwell unified electricity and magnetism through a set of four fundamental mathematical equations known as Maxwell's equations.
☛ A crucial insight added by Maxwell was the concept of displacement current, showing that a time-varying electric field produces a magnetic field, just as Faraday's law showed that a time-varying magnetic field produces an electric field.
☛ This mutual regeneration creates self-sustaining electromagnetic (EM) waves that do not require any physical medium and can propagate through a vacuum at the speed of light (approximately 3 × 108 m/s).
☛ Maxwell's equations also mathematically proved that electromagnetic waves are transverse in nature, where both electric and magnetic field vectors oscillate perpendicular to each other and perpendicular to the direction of propagation.
Extra Exam-Relevant Facts:
☛ Maxwell’s Four Equations: These include Gauss's Law for Electricity, Gauss's Law for Magnetism, Faraday's Law of Induction, and the Ampere-Maxwell Law.
☛ Speed of EM Waves: The speed of electromagnetic waves in a vacuum is given by the relation c = 1 / √(μ₀ε₀), where μ₀ is the permeability of free space and ε₀ is the permittivity of free space.
☛ Heinrich Hertz: The experimental confirmation of electromagnetic waves predicted by Maxwell was first demonstrated by Heinrich Hertz in 1887.
☛ Electromagnetic waves carry both energy and momentum, and can exert radiation pressure on surfaces they strike.
Important One-Liners for Upcoming Exams:
☛ Who predicted the existence of electromagnetic waves theoretically? → James Clerk Maxwell
☛ What term was introduced by Maxwell to modify Ampere's Circuital Law? → Displacement Current
☛ What is the angle between the electric field and magnetic field in an EM wave? → 90 degrees (Perpendicular)
☛ Who experimentally produced and detected electromagnetic waves for the first time? → Heinrich Hertz
☛ Which fundamental law indicates that magnetic monopoles do not exist? → Gauss's Law for Magnetism