Question

Which of the following orbits is a possible orbit for a planet?

• A.

  

• B.

  

• C.

  

• D.

  

Answer 1

The correct option is D

Step 1: Explaining the principle:

From Kepler's first law of planetary motion, we know that

All the planets move around the Sun in an elliptical orbit.

Sun at one of its foci of all the planets.

A radius vector joining any particular planet to the Sun sweeps out equal areas in equal intervals of time.

As we know that an ellipse can be represented by the formula

$r=\frac{P}{1+\mathrm{\epsilon }\mathrm{Cos\theta }}$

Here P is the semi latus rectum.

$\theta$ is the angle to the planet's current position from its closest approach.

$\epsilon$ is the eccentricity.

Step 2: Explanation of incorrect options:

Option (a) and (b): the sun is not in the focus of the elliptical path.

Option (c): Sun is in the orbit of the planet which is never true.

Step 3: Explanation of correct option:

Option (d): represents the possible orbit of a planet.

So, the correct answer is (d)