The electric field of a radio wave is given by E^→=E_0sin(kz−ωt)(^i+^j). Give a unit vector in the direction of the magnetic field at a place and time where sin(kz−ωt) is positive.
Keely Rivers
Answered question
2023-01-14
Answer & Explanation
tappahtappahwf6
Beginner2023-01-15Added 11 answers
Given,
→E=E0sin(kz−ωt)(^i+^j)
The unit vector of electric field is,
(^i+^j)√2
→E×→B is in direction of wave propagation
Given, sin(kz−ωt) is+ve, Thus unit vector in the direction of →B will be in the same plane ⊥→E
Therefore, the unit vector along magnetic field is,
−^i+^j√2<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}-->Hence, (C) is the correct answer.
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