JEE Main 2022 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 28 June 2022, Shift 1, Physics Q35

Question 35 of 90 in this shift, Physics question 5 of 30, Section A.

Two planets A and B of equal mass are having their period of revolutions

\mathrm{T_A}

and

\mathrm{T_B}

such that

\mathrm{T_A} = 2\mathrm{T_B}

. These planets are revolving in the circular orbits of radii

\mathrm{r_A}

and

\mathrm{r_B}

respectively. Which out of the following would be the correct relationship of their orbits?

(1) $2\mathrm{r_A^2} = \mathrm{r_B^3}$
(2) $\mathrm{r_A^3} = 2\mathrm{r_B^3}$
(3) $\mathrm{r_A^3} = 4\mathrm{r_B^3}$ Official answer
(4) $\mathrm{T_A^2} - \mathrm{T_B^2} = \frac{\pi^2}{GM}\left(\mathrm{r_B^3} - 4\mathrm{r_A^3}\right)$

Official answer

Option 3

NTA final key.

Chapter: Gravitation
Topic: Orbital Mechanics
Idea tested: Kepler's Laws

Same idea in other shifts

Asked 7× in all

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.