Laws of Motion Exe-3E Short Answer Physics Class-9 ICSE Selina Publishers

Laws of Motion Exe-3E Gravitation Short Answer Type for Class-9 ICSE Concise Physics. There is the solutions of Short Answer type Questions of your latest textbook which is applicable in 2023-24 academic sessionVisit official Website CISCE for detail information about ICSE Board Class-9.

Laws of Motion Exe-3E Gravitation Short Answer

(ICSE Class – 9 Physics Concise Selina Publishers)

 Board ICSE Class 9th Subject Physics Writer / Publication Concise selina Publishers Chapter-3 Laws of Motion Exe – 3E Gravitation Topics Solution of Exe-3(E) Short Answer Type Academic Session 2023-2024

Ch-3 Laws of Motion Physics Class-9 ICSE Concise

Page 89

Question 1. How does the gravitational force of attraction between two masses depend on the distance between them?

The gravitational force of attraction between two masses is inversely proportional to the square of distance between them.

Question 2. What is the importance of law of gravitation?

The gravitational force of attraction is significant to explain the motion of heavenly bodies, e.g. motion of planets around the Sun, motion of the Moon around the Earth etc.

Question 3. What do you understand by the term force due to gravity?

The force with which the Earth attracts a body towards its centre is called the force due to gravity.

(Laws of Motion Exe-3E Short Class-9 ICSE)

Question 4. Write an expression for the force due to gravity on a body of mass m and explain the meaning of symbols used in it.

The force due to gravity on a body of mass m kept on the surface of Earth (mass=M and radius=R) is equal to the force of attraction between the Earth and that body.

F∈ (Gm x M)/d²

Question 5. How is the acceleration due to gravity on the Earth’s surface related to the mass and radius ?

Let g be the acceleration due to gravity on the Earth’s surface (mass = M and radius = R).

Then, g=gM/R²

Question 6. Define the terms mass and weight.

Mass: The mass of a body is the quantity of matter it contains.

Weight: The weight of a body is the force with which the Earth attracts it.

Question 7. Distinguish between mass and weight.

Mass is a scalar quantity, but weight is a vector quantity. It is the measure of the quantity of matter contained in a body, but weight is the measure of force with which the Earth attracts the body. While Mass of a body is always constant but weight varies from place to place.