Hubble's law: If a galaxy is receding from us at 0.10c. Use Hubble's law to estimate the distance to this galaxy if the Hubble constant is 22 km/s per million light-years. (c = 3.00 × 10⁸ m/s, 1 ly = 9.461 × 10¹⁵ m, 1 y = 3.156 × 10⁷ s) A) 1.4 × 10⁹ ly B) 6.6 × 10⁵ ly C) 6.6 × 10⁵ Mly D) 2.2 Mly E) 1.4 × 10⁷ Mly

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Hubble's law is v = H0 * d, where v is the velocity of the galaxy, H0 is the Hubble constant, and d is the distance to the galaxy. Given v = 0.10c = 0.10 * 3.00 × 10^8 m/s and H0 = 22 km/s/Mly = 22,000 m/s/Mly, we solve for d: d = v / H0 = (0.10 * 3.00 × 10^8 m/s) / (22,000 m/s/Mly) = 1.36 × 10^6 Mly = 1.4 × 10^19 ly.

Hubble's Law: If a Galaxy Is Receding from Us at 0.10c