Question

When the Voyager 2 spacecraft sent back pictures of Neptune during its flyby of that planet in 1989, the spacecraft’s radio signals traveled for 4 hours at the speed of light to reach Earth. How far away was the spacecraft? Give your answer in kilometers, using powers-of-ten notation. (Speed of light c is 3.00 × 108 m s−1 .)

Answer 1

Answer:

$d=4.32\times10^{12}m$

Explanation:

The radio signals must travel for t=4 hours at $c=3\times10^8m/s$. Since an hour has 60 minutes and a minute has 60 seconds we have that 4 hours are 4(60)(60) seconds = 14400s. We have the speed of light c=300000000m/s, so we use the definition of velocity in terms of distance travelled and time taken v=d/t , which in our case is v=c, and solving for d we have:

$d=vt=(300000000m/s)(14400s)=4320000000000m=4.32\times10^{12}m$