Radio waves of speed $3.0 \times 10^{8} m s^{- 1}$ reflected off the moon and received back on the earth, the time elapsed between the sending of the signal and receiving it back on the earth’s surface is $2.5 s$ . What is the distance between moon and the earth?

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Solution

Step-1 Given
Speed of radio wave $= 3.0 \times 10^{8} m / s$
Total time $= 2.5 s$
Step-2 Finding the distance between moon and earth
Total distance $= S p e e d o f r a d i o w a v e \times T o t a l t i m e$
$= 3.0 \times 10^{8} \times 2.5$
Total distance $= 7.5 \times 10^{8} m$
$∵$ Radio wave is traveling from the earth's surface to the moon and reflect back from the moon to earth.
$∴$ Distance between moon and earth $= \frac{T o t a l d i s \tan c e}{2}$
$= \frac{7.5 \times 10^{8}}{2}$
$= 3.75 \times 10^{8} m$
Hence, the distance between the moon and the earth is $3.75 \times 10^{8} m$ .

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Radio waves of speed 3.0×108ms-1reflected off the moon and received back on the earth, the time elapsed between the sending of the signal and receiving it back on the earth’s surface is 2.5s. What is the distance between moon and the earth?

Radio waves of speed $3.0 \times 10^{8} m s^{- 1}$ reflected off the moon and received back on the earth, the time elapsed between the sending of the signal and receiving it back on the earth’s surface is $2.5 s$ . What is the distance between moon and the earth?