Two coherent waves of intensities I₁ and I₂ interfere. Which pair correctly gives the maximum and minimum possible resultant intensities?
Options

Question

Two coherent waves of intensities I₁ and I₂ interfere. Which pair correctly gives the maximum and minimum possible resultant intensities?

G1 Physics · Accepted Answer

Maximum intensity occurs for φ = 0. Therefore, Iₘₐₓ = I₁+I₂+2√(I₁I₂) = (√I₁+√I₂)². Minimum intensity occurs for φ = π. Therefore, Iₘᵢₙ = I₁+I₂−2√(I₁I₂) = (√I₁−√I₂)². Correct option: B.