The speed of light in a vacuum is about 3. 0 x 10 ^8 meters per second.
The speed of light can also be measured in kilometers per second or miles per second.
(Note: 1 m = 0.001 km and 1 m is about 0.00062 mi).
1. The speed of light in kilometers per second.
[tex]\begin{gathered} \text{Given }1\text{ m = 0.001 km,} \\ 3.0\text{ x 1}0^8m=3.0x10^{8\text{ }}\text{ x 0}.001=300,000km=3x10^5 \end{gathered}[/tex][tex]\text{Hence, the sp}eedoflightis3x10^{\text{ 5}}\text{ kilometers per second}[/tex]2. The speed of light in miles per second.
Given 1 m = 0.00062 miles
[tex]\begin{gathered} 3x10^8m=3x10^{8\text{ }}X0.00062=186,000=1.86X10^{5\text{ }}miles \\ \text{Hence, the sp}eedoflightisalso1.86x10^{5\text{ }}miles\text{ per second.} \end{gathered}[/tex]
