Q 11-07-036NEETJEE MainMedium
The height of a geostationary satellite above the Earth's surface is about $36000$ km. Taking the Earth's radius as $6400$ km, the orbital speed of such a satellite is about
Answer: (D) $3.1$ km/s
$r = 42400$ km and $T = 24$ h $= 86400$ s:
$$v = \frac{2\pi r}{T} = \frac{2\pi \times 42400}{86400} \approx 3.1\ \text{km/s}$$
Solution by Sreeraj P, M.Sc Physics