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The speed of light in a vacuum is 2. 998×108 m/s. What is its speed in kilometers per hour (km/h)?.

User Axsuul
by
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2 Answers

6 votes

Answer: 1.118x10^7

CHEMISTRY (conversion for miles/minute)

Step-by-step explanation:

Using conversions from meters - miles & seconds - minutes

2.998 x 10^8 m/s x 1 mi/1609m x 60s/1 min

using this equation the meters and seconds cancel out giving you miles per minute

After calculating you get 11179614, which you turn into scientific notation

This turns the problem into 1.1179614 BUT since the original equation has 4 sig figs, (2.998 is 4 sig figs) your final answer should have 4 sig figs

because you also moved the decimal 7 places to turn it into scientific notation, that will be the exponent in your final answer as well

so when you are computing your final answer, you take the first 4 digits (of 1.1179614) which is 1.118 (the 8 because you're rounding) and you finally have the equation

1.118 x 10^7 miles/minute

User Belle Tian
by
4.3k points
11 votes

Step-by-step explanation:

You know that 3,600secs makes an hr and 1000m makes a km.

You simply multiply by 3,600sec and divide by 1000m

=

2.998x10⁸m/s x 3,600s/1hr x 1km/1000m

= 1.079 x 10⁹km/hr.

User Mike Duncan
by
3.6k points