A light source approaches the observer with velocity 0.8 c. The doppler shift for the light of wavelength 5500 Å is
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A light source approaches the observer with velocity 0.8 c. The doppler shift for the light of wavelength 5500 Å is

G1 Physics · Accepted Answer

Step 1: For light, use relativistic Doppler when speed is a sizable fraction of c; for v ≪ c, Δλ/λ ≈ v/c. Step 2: Red shift means recession and blue/violet shift means approach. Step 3: Substitute the given speed. Final: C: 3167 Å.