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Light travels at a speed of about 3.0 108 m/s.(a) How many miles does a pulse of light travel in a time interval of 0.1 s, which is about the blink of an eye?Δx = mi(b) Compare this distance to the diameter of Earth. (Use 6.38 106 m for the radius of the Earth.)ΔxDE =

Light travels at a speed of about 3.0 108 m/s.(a) How many miles does a pulse of light-example-1
User Etienne Perot
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1 Answer

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Given:

Speed of light = 3 x 10⁸ m/s

Let's solve for the following:

• (a). How many miles does a pulse of light travel in a time interval of 0.1 s, which is about the blink of an eye?

Apply the formula:


\Delta x=v*t

Where:

v is the speed of light

t is the time.

Thus, we have:


\begin{gathered} \Delta x=3.0*10^8*0.1 \\ \\ \Delta x=3.0\operatorname{*}10^7\text{ m} \end{gathered}

Now let's convert the answer from meters to miles.

Where:

1 mile = 1609.34 meters


\begin{gathered} 3.0*10^7=(3.0*10^7)/(1609.34) \\ \\ =18641.14\text{ mi} \end{gathered}

Δx = 18641.14 mi

• (b). Compare this distance to the diameter of Earth.

Apply the formula:


(\Delta x)/(D_E)=(\Delta x)/(2*r)

Where:

r = 6.38 x 10⁶ m.

Thus, we have:


(\Delta x)/(D_E)=(3.0*10^7)/(2*6.38*10^6)=2.35

ANSWER:

• (a). 18641.14 mi

,

• (b). 2.35

User Pavlos
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