Question

1. apply concepts light travels at a speed of 3.00 × 10^{10} cm/s. what is the speed of light in kilometers/hour?

Explanation:

Step1: Convert centimeters to kilometers

1 kilometer = 100000 centimeters. So, to convert from cm to km, divide by $10^{5}$. The speed is $3.00\times 10^{10}$ cm/s. In km/s, it is $\frac{3.00\times 10^{10}}{10^{5}}$ km/s.
$$\frac{3.00\times 10^{10}}{10^{5}}=3.00\times 10^{10 - 5}=3.00\times 10^{5}\text{ km/s}$$

Step2: Convert seconds to hours

1 hour = 3600 seconds. To convert from km/s to km/h, multiply by 3600 (or $3.6\times 10^{3}$).
$$3.00\times 10^{5}\text{ km/s}\times3.6\times 10^{3}\text{ s/h}=(3.00\times3.6)\times10^{5 + 3}\text{ km/h}$$
$$10.8\times 10^{8}\text{ km/h}=1.08\times 10^{9}\text{ km/h}$$

Answer:

$1.08\times 10^{9}$ km/h