Answer to Question #181841 in Quantum Mechanics for Olamide Adeyemi

Question

Light takes 4.5 years to reach us from the nearest star. If the velocity of light is 3 ×10^8 ms-1, how far away is the star? A rocket first outside the Earth’s atmosphere in space accelerates at 30ms-2 for a week (7 days). How long will it take for the rocket to reach the star? (Ignore any gravitational attraction).

Answer 1

i) v = 3$\times$10⁸ $\frac{m}{s}$= 9.47$\times$10¹² $\frac{km}{year}$

l = 9.467$\times$10¹²$\times$4.5 = 4.26$\times$10¹³ km

ii) v = 30$\times$(7$\times$24$\times$3600) = 1.8144$\times$10⁷ $\frac{m}{s}$ = 18144 $\frac{km}{s}$

t = $\frac{4.26\times10^{13}}{18144}$ = 2.35$\times$10⁹ years