Sharp el-9950

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Chapter 3
Manual Calculations
1. Try it!
The speed of light is known to be 186,282 miles
(approximately 300,000 kilometers) per second.
That means light can go around the earth 7 and
ahalftimeswithinasecond!
Supposeyouarestandingattheequator.While
the earth rotates over the period of one day, you
also rotate around the globe at a certain speed.
Knowing the facts above, can you figure out
how fast you are traveling, in miles per hour?
Sincedistancetraveled=averagespeed
×
time taken, the following
equation can be formed to find out the circumference of the earth (x
miles):
x
×
7.5 = 186282
Then,
x = 186282 ÷ 7.5
Sinceyouknowtheearthturnsaroundonceaday(whichmeans,
in24hours),dividetheabove“x”with24togetavalueinmilesper
hour.
24
×
v = x
v =
x
24