Given:
The speed of light is 2.998 x 10⁸ m/s
Question:
How long does it take light to travel 30 cm?
Just leave your answer as a math expression.
The Process:
Recall [tex]\boxed{ \ 1 \ meter = 100 \ cm \ }[/tex]
Let us convert cm to m for distance traveled:
[tex]\boxed{ \ 30 \ cm \times \frac{1 \ m}{100 \ cm} \rightarrow 0.3 \ m \ }[/tex]
The relationship between distance, speed, and time is as follows:
[tex]\boxed{ \ distance = speed \times time \ }[/tex]
Because in this case you are being asked how long or time it takes, make it the subject.
[tex]\boxed{ \ time = \frac{distance}{speed} \ }[/tex]
[tex]\boxed{ \ time = \frac{0.3 \ m}{2.998 \times 10^8 \ m/s} \ }[/tex]
Rounding the quotient produces:
[tex]\boxed{ \ time = 0.1 \times 10^{-8} \ s \ }[/tex]
Adjust it again to fit the scientific notation.
The result is [tex]\boxed{ \ time = 1.0 \times 10^{-9} \ s \ }[/tex]
As a mathematical expression, the time taken for light is
[tex]\boxed{ \ time = \frac{0.3 \ m}{2.998 \times 10^8 \ m/s} \ }[/tex]
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