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#remote control

2 public questions tagged with this topic.

Which electromagnetic waves are used in remote switches of household electronic systems?

**Hertz experiment** used induction coil connected to two rods with gap, spark produced oscillating charge, emitted EM wave, received by loop with gap sparking when E induced, measured wavelength by standing wave, demonstrated EM wave properties, validating Maxwell. Infrared waves are widely used in remote switches for devices like TVs and hi-fi systems, as mentioned in the document. Using c = fλ, E₀/B₀ = c, I_d = ε₀ dΦ_E/dt, and spectrum classification λ = c/f, evaluation yields Infrared waves, illustrating EM wave transverse nature and Maxwell's displacement current concept.

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

Why are infrared waves used in remote switches of household electronic systems?

**Infrared waves** λ≈700 nm to 1 mm, f≈10¹² to 4×10¹⁴ Hz, produced by hot bodies and molecular vibrations, wavelength range as per document 700 nm-1 mm, used in remote sensing because IR penetrates haze, thermal imaging detects IR emitted by objects, remote controls, effective for sensing temperature. The document mentions that infrared waves are emitted by electronic devices like LEDs and are widely used in remote switches due to their ability to transmit signals effectively over short distances. Using c = fλ, E₀/B₀ = c, I_d = ε₀ dΦ_E/dt, and spectrum classification λ = c/f, evaluation yields They transmit signals effectively, illustrating EM wave transverse

Ref: NCERT > Physics Book > Electromagnetic Waves > Infrared, Visible Light and Applications