An observer moves toward a stationary microwave source with speed c/2. The source frequency is 10 GHz. What frequency does the observer measure? Take c = 3 × 10⁸ m s⁻¹.
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An observer moves toward a stationary microwave source with speed c/2. The source frequency is 10 GHz. What frequency does the observer measure? Take c = 3 × 10⁸ m s⁻¹.

G1 Physics · Accepted Answer

Step 1: Because the observer speed is c/2, use relativistic Doppler for approach: f' = f√[(1+β)/(1−β)], β=0.5. Step 2: f' = 10√3 GHz ≈ 17.3 GHz. Final: D.