# NCERT Question 6 - Chapter 10 Class 9 - Gravitation (Term 2)

Last updated at May 30, 2019 by

Last updated at May 30, 2019 by

Transcript

NCERT Question 6 What happens to the force between two objects, if (i) the mass of one object is doubled? (ii) the distance between the objects is doubled and tripled? (iii) the masses of both objects are doubled? We know that gravitational force between two objects is given by, F = 𝐺𝑀𝑚/𝑟^2 where G = Gravitational constant M = Mass of object 1 m = Mass of object 2 r = Distance between the two objects When mass of one object is doubled Let Mass of Object 1 be doubled New Mass of Object 1 = 2M Thus, New Force = (𝐺 × 2𝑀 × 𝑚)/𝑟^2 = 2𝐺𝑀𝑚/𝑟^2 = 2 × Old Force ∴ If mass of one object is doubled, the force is also doubled Distance between object is doubled and tripled Distance is doubled So, New Distance = 2r New Force = 𝐺𝑀𝑚/(2𝑟)^2 = 𝐺𝑀𝑚/(4𝑟^2 ) = 1/4 × Old Force Distance is tripled So, New Distance = 3r New Force = 𝐺𝑀𝑚/(3𝑟)^2 = 𝐺𝑀𝑚/(9𝑟^2 ) = 1/9 × Old Force Therefore, When distance is doubled, Force becomes 𝟏/𝟒 times of Old Force When distance is tripled, force becomes 𝟏/𝟗 times of Old Force (iii) When mass of both objects is doubled New Mass of Object 1 = 2M New Mass of Object 2 = 2m Thus, New Force = (𝐺 × 2𝑀 × 2𝑚)/𝑟^2 = 4𝐺𝑀𝑚/𝑟^2 = 4 × Old Force ∴ If mass of both objects is doubled, the force becomes four times

NCERT Questions

NCERT Question 1

NCERT Question 2 Important

NCERT Question 3

NCERT Question 4

NCERT Question 5 Important

NCERT Question 6 Important You are here

NCERT Question 7

NCERT Question 8 Important

NCERT Question 9

NCERT Question 10

NCERT Question 11 Important

NCERT Question 12 Important

NCERT Question 13 Important

NCERT Question 14 Important

NCERT Question 15

NCERT Question 16

NCERT Question 17 Important

NCERT Question 18 Important

NCERT Question 19 Important

NCERT Question 20 Important

NCERT Question 21 Important

NCERT Question 22

Class 9

Chapter 10 Class 9 - Gravitation (Term 2)

About the Author

CA Maninder Singh

CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo