In an electromagnetic field, which one of the following remains invariant under Lorentz transformation?

A. $$\overrightarrow {\bf{E}} \times \overrightarrow {\bf{B}} $$

B. E2 - c2B2

C. B2

D. E2

Answer: Option B

This Question Belongs to Engineering Physics >> Electromagnetic Theory

Join The Discussion

Related Questions on Electromagnetic Theory

Which one of the following current densities, $$\overrightarrow {\bf{J}} $$ can generate the magnetic vector potential $$\overrightarrow {\bf{A}} = \left( {{y^2}{\bf{\hat i}} + {x^2}{\bf{\hat j}}} \right)?$$

A. $$\frac{2}{{{\mu _0}}}\left( {x{\bf{\hat i}} + y{\bf{\hat j}}} \right)$$

B. $$ - \frac{2}{{{\mu _0}}}\left( {{\bf{\hat i}} + {\bf{\hat J}}} \right)$$

C. $$ - \frac{2}{{{\mu _0}}}\left( {{\bf{\hat i}} - {\bf{\hat j}}} \right)$$

D. $$\frac{2}{{{\mu _0}}}\left( {x{\bf{\hat i}} - y{\bf{\hat j}}} \right)$$