JEE Main201910 Apr 2019Morning ShiftPhysicsElectromagnetic WavesActual
The electric field of a plane electromagnetic wave is given by E → = E 0 i ^ cos ⁡ k z c o s ⁡ ( ω t ) The corresponding magnetic field B → is then given by:
Options
- AB → = E 0 C j ^ cos k z s i n ( ω t )
- BB → = E 0 C k ^ sin k z c o s ( ω t )
- CB → = E 0 C j ^ sin k z s i n ( ω t )
- DB → = E 0 C j ^ sin k z c o s ( ω t )
Correct answer
C. B → = E 0 C j ^ sin k z s i n ( ω t )
Step-by-step solution
E → = E 0   i ^   c o s   k z   c o s ω t E → = E 0 2   i ^   c o s   k z - ω t + E 0 2 i ^   c o s k z + ω t B → = E 0 2 C   j ^   c o s   k z - ω t + E 0 2 C j ^   c o s k z + ω t = E 0 2 C j ^   2   s i n   k z s i n ω t = E 0 C j ^     s i n   k z s i n ω t