Explain Kepler’s first (Law of Orbits) law for planetary motion.
Law of Orbits :
All planets move in elliptical orbits with the sun situated at one of the foci of the ellipse.
An ellipse traced out by a planet around the sun. The closest point is $P$ and farthest point is $A$. $P$ is called the Perihelion and $\mathrm{A}$ the aphelion. The semi major axis is half the distance $AP$.
This law was a deviation from the Copernican model which allowed only circular orbits. (The ellipse of which the circle is a special case is a closed curve).
Which of the following quantities does not depend upon the orbital radius of the satellite
The rotation period of an earth satellite close to the surface of the earth is $83$ minutes. The time period of another earth satellite in an orbit at a distance of three earth radii from its surface will be .......... $\min$
If satellite is shifted towards the earth. Then time period of satellite will be
The ratio of kinetic energy of a planet at perigee and apogee during its motion around the sun in elliptical orbit of eccentricity $e$ is ..........
If the radius of earth's orbit is made $1\frac{1}{4}$, the duration of an year will become