An electromagnetic wave of frequency v=3.0MHz passes from vacuum into a dielectric medium with relative permittivity ε=4.0 Then:
Held on 30 Apr 2013 · Verified 9 Jul 2026.
Wavelength is double and frequency become half.
Wavelength is halved and frequency remains unchanged.
Wavelength and frequency both remain unchanged.
Wavelength is doubled and frequency unchanged.
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