NEET 2021
- Exam
- NEET
- Year
- 2021
- Subject
- Physics
- Chapter
- Electromagnetic Waves
NEET 2021 · Physics · Electromagnetic Waves
For a plane electromagnetic wave propagating in x -direction, which...
For a plane electromagnetic wave propagating in -direction, which one of the following combinations gives the correct possible directions for the electric field () and magnetic field () respectively?
Options
- A\overset{^}{j} + \overset{^}{k}, \overset{^}{j} + \overset{^}{k}
- B- \overset{^}{j} + \overset{^}{k}, - \overset{^}{j} - \overset{^}{k}
- C\overset{^}{j} + \overset{^}{k}, - \overset{^}{j} - \overset{^}{k}
- D- \overset{^}{j} + \overset{^}{k}, - \overset{^}{j} + \overset{^}{k}
Correct answer
B. - \overset{^}{j} + \overset{^}{k}, - \overset{^}{j} - \overset{^}{k}
Step-by-step solution
Direction
(i) ( \overset{^}{j} + \overset{^}{k} ) \times ( \overset{^}{j} + \overset{^}{k} ) = 0
(ii) ( - \overset{^}{j} + \overset{^}{k} ) \times ( - \overset{^}{j} - \overset{^}{k} )
= 0 + \overset{^}{ı} - ( - \overset{^}{ı} ) + 0
= 2\overset{^}{ı}
(iii) ( \overset{^}{j} + \overset{^}{k} ) \times ( - \overset{^}{j} - \overset{^}{k} ) = 0
(iv) ( - \overset{^}{j} + \overset{^}{k} ) \times ( - \overset{^}{j} + \overset{^}{k} )