Use app×
Join Bloom Tuition
One on One Online Tuition
JEE MAIN 2025 Foundation Course
NEET 2025 Foundation Course
CLASS 12 FOUNDATION COURSE
CLASS 10 FOUNDATION COURSE
CLASS 9 FOUNDATION COURSE
CLASS 8 FOUNDATION COURSE
0 votes
9.3k views
in Gravitation by (30 points)
edited by

Two planets \( A \) and \( B \) of equal mass are having their period of revolutions \( T _{ A } \) and \( T _{ B } \) such that \( T_{A}=2 T_{B} \). These planets are revolving in the circular orbits of radii \( r _{ A } \) and \( r _{ B } \) respectively. Which out of the following would be the correct relationship of their orbits? 

(A) \( 2 R_{ A }^{2}= R _{ B }^{2} \) 

(B) \( R _{ A }^{3}=2 R _{ B }^{3} \) 

(C) \( R_{ A }^{3}=3 R_{ B }^{3} \)

(D) \({R_A}^3 = {4 R_B}^3\)

Please log in or register to answer this question.

2 Answers

0 votes
by (15 points)


Ta /Tb = ra3 / rb3


ra3 = 4rb3

0 votes
by (54.6k points)

Correct option is (D) \({R_A}^3 = {4 R_B}^3\)

We know

\(T^2 \propto R^3\)

\(\frac{{T_A}^2}{{T_B}^2} = \frac{{R_A}^3}{{R_B}^3} \)

\(\because T_A = 2T_B\)

\(\frac{{4T_B}^2}{{T_B}^2} = \frac{{R_A}^3}{{R_B}^3} \)

\({R_A}^3 = {4 R_B}^3\)

Welcome to Sarthaks eConnect: A unique platform where students can interact with teachers/experts/students to get solutions to their queries. Students (upto class 10+2) preparing for All Government Exams, CBSE Board Exam, ICSE Board Exam, State Board Exam, JEE (Mains+Advance) and NEET can ask questions from any subject and get quick answers by subject teachers/ experts/mentors/students.

...