The time period of a satellite in a circular orbit of radius R is T. The period of another satellite in a circular orbit of radius 9R is :
Solution
<p>Kepler's Third Law states that the square of the period of a satellite's orbit is proportional to the cube of the semi-major axis of its orbit. This relationship can be written as:</p>
<p>$T^2 \propto r^3$</p>
<p>where:</p>
<ul>
<li>$T$ is the orbital period</li>
<li>$r$ is the radius of the circular orbit (which serves as the semi-major axis in this case)</li>
</ul>
<p>Considering two satellites, one with period $T$ and radius $R$, and another with unknown period $T'$ and radius $9R$, we can form an equation:</p>
<p>$\frac{{T'}^2}{T^2} = \frac{(9R)^3}{R^3}$</p>
<p>This simplifies to:</p>
<p>$\frac{{T'}^2}{T^2} = 729$</p>
<p>Taking the square root of both sides, we get:</p>
<p>$T' = T \times \sqrt{729} = T \times 27$</p>
<p>So, the period of another satellite in a circular orbit of radius $9R$ is $27T$.</p>
About this question
Subject: Physics · Chapter: Gravitation · Topic: Kepler's Laws
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