+233 Alpha Centauri is the closest star system to earth. Alpha Centauri is about 10^13 kilometers away from earth. A spacecraft leaves Earth and travels at an average speed of 10^4 meters per second. About how many years would it take the spacecraft to reach Alpha Centauri?
Please Tell me how you got your answer.
+128406 10^13 km = [10^13 * 1000 ] m = [ 10^13 * 10^3 ] m = 10^16 m....so....
10^16m / [10^4 m /s] =
10^12 seconds
Seconds in a year = 60min x 60 min/hr x 24hr/day x 365 days/yr =
60 * 60 * 24 * 365 = 31,536,000 seconds / yr
So
10^12 s / [ 31,536,000 s / yr ] ≈ 31709.8 years
10^4 meters per sec./ 1,000 meters =10 km/second - the speed of the spaceship.
10^13 km to Alpha C. / 10 km/sec =10^12 seconds to get to Alpha C. Since there are:
365 days x 24 hours x 60 minutes x 60 seconds =31,536,000 seconds in 1 year. Therefore:
10^12 seconds / 31,536,000 sec. in 1 year =31,709.79 - years for the spaceship to get to Alpha C.
