An elliptical satellite orbit has perigee R and apogee 3R. A circular satellite around the same planet has radius 2R. If their periods are $T_e$ and $T_c,$ then $T_e/T_c$ is:
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An elliptical satellite orbit has perigee R and apogee 3R. A circular satellite around the same planet has radius 2R. If their periods are T_e and T_c, then T_e/T_c is:

G1 Physics · Accepted Answer

The ellipse has semi-major axis a=(R+3R)/2=2R. Kepler's third law gives T²∝a³. The circular orbit also has semi-major axis 2R, so the periods are equal: T_e/T_c=1.