Concepts Of Physics MCQ Edition [Volume 2]PhysicsElectromagnetic Waves
The maximum electric field of the sunlight reaching the earth is 810 V m ⁻¹ . Determine the maximum magnetic field present in this light.
Options
- A2.7 10⁻⁷ T
- B2.7 10⁻⁶ T
- C8.1 10⁻⁶ T
- D8.1 10⁻⁷ T
Correct answer
B. 2.7 10⁻⁶ T
Step-by-step solution
The relationship between the maximum electric field E₀ and the maximum magnetic field B₀ in an electromagnetic wave is given by: E₀ = c B₀ where c is the speed of light in vacuum, c = 3 10^8 m s ⁻¹ . Given E₀ = 810 V m ⁻¹ . Substituting the values: B₀ = E₀ c B₀ = 810 3 10^8 B₀ = 270 10⁻⁸ T B₀ = 2.7 10⁻⁶ T