Question

A particle of charge $ -16\,\times {{10}^{-18}}C $ moving with velocity $ 10\,m{{s}^{-1}} $ along the $ x $ -axis enters a region where a magnetic field of induction B is along the y-axis and an electric field of magnitude $ \text{1}{{\text{0}}^{\text{4}}}\text{V/m} $ is along the negative z-axis. If the charged particle continues moving along the $ x $ -axis, the magnitude of B is

• A. $ {{10}^{16}}\,Wb/{{m}^{2}} $
• B. $ {{10}^{5}}\,Wb/{{m}^{2}} $
• C. $ {{10}^{3}}\,Wb/{{m}^{2}} $
• D. $ {{10}^{-3}}\,Wb/{{m}^{2}} $

Answer 1

Answer: (C)

As particle is moving without deviation, therefore $ Eq=Bqv $ $ \therefore $ $ B=\frac{E}{v}=\frac{{{10}^{4}}}{10} $ $ ={{10}^{3}}Wb/{{m}^{2}} $