#light

Production of EM Waves and Hertz Experiment

What did Maxwell's equations predict about the nature of light?

**Aerials produce radio waves** by rapid acceleration/deceleration of electrons in antenna driven by AC, frequency equals driving frequency, for 60 MHz, λ=c/f=3×10⁸/60×10⁶=5 m, half-wave antenna length λ/2=2.5 m, efficient radiation when antenna size comparable to λ. The document notes that Maxwell's equations predicted that light is an electromagnetic wave, confirmed by the fact that the speed of EM waves matched the speed of light. Using c = fλ, E₀/B₀ = c, I_d = ε₀ dΦ_E/dt, and spectrum classification λ = c/f, evaluation yields Light is an electromagnetic wave, illustrating EM wave transvers

Ref: NCERT > Physics Book > Electromagnetic Waves > Production of EM Waves and Hertz Experiment

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Displacement Current and Ampere-Maxwell Law

What enables electromagnetic waves to propagate through vacuum?

**Displacement current** I_d = ε₀ dΦ_E/dt, Φ_E = ∫ E·dA electric flux (V·m), ε₀=8.85×10⁻¹² F/m, ensures continuity of current in charging capacitor where conduction current stops between plates, I_d equals conduction current in wires, 3 A conduction ⇒ 3 A displacement, maintaining Ampere's law ∮ B·dl = μ₀(I_c+I_d). The document states that electromagnetic waves are self-sustaining oscillations of electric and magnetic fields, requiring no material medium for propagation. Using c = fλ, E₀/B₀ = c, I_d = ε₀ dΦ_E/dt, and spectrum classification λ = c/f, evaluation yields Self-sustaining electric a

Ref: NCERT > Physics Book > Electromagnetic Waves > Displacement Current and Ampere-Maxwell Law

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PHYSICS

What is the frequency of light with a wavelength of 595 nm in air, given the speed of light in air is 3.0 × 10⁸m/s ?

Given: What is the frequency of light with a wavelength of 595 nm in air, given the speed of light in air is 3.0 × 10⁸m/s ? These values define the system as per NCERT data. Formula: Frequency nu = c/lambda. This is standard NCERT relation. Substitution & Calculation: lambda = 5.95 × 10⁻⁷m, c = 3.0 × 10⁸m/s . nu = frac3.0 × 10⁸⁵.95 × 10⁻⁷approx 5.04 × 10¹⁴Hz . Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

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PHYSICS

What determines the intensity of light in the wave picture?

In the wave picture, intensity is proportional to the square of the amplitude of the wave. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Physics Textbook for Class XI and XII, Chapter: Relevant Physics topic covering fundamental principles,

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