NEET Solved Paper 2018 Question 18
Question: An em wave is propagating in a medium with a velocity $ \overrightarrow{{}v}=v\widehat{i} $ . The instantaneous oscillating electric field of this em wave is along $ \text{+y} $ axis. Then the direction of oscillating magnetic field of the em wave will be along [NEET - 2018]
Options:
A) -y direction
B) +z direction
C) -z direction
D) -x direction
Show Answer
Answer:
Correct Answer: B
Solution:
- $ \overrightarrow{{}E}\times \overrightarrow{{}B}=\overrightarrow{{}V} $ $ (E\overrightarrow{{}j})\times (\overrightarrow{{}B})=v\widehat{i} $ So, $ \overrightarrow{{}B}\text{=B}\widehat{k} $ Direction of propagation is along +z direction.
