NCERT Solutions for Class 9 Science Chapter 9 : Force And Laws Of Motion

Content Curator

The NCERT Solutions for Class 9 Science Chapter 9 Force And Laws Of Motion are provided in this article below. Some of the important concepts of Class 9 Science Chapter 9 Force and Laws of Motion are:

Download: NCERT Solutions for Class 9 Science Chapter 9 pdf

NCERT Solutions for Class 9 Science Chapter 9

NCERT Solutions for Class 9 Science chapter 9

Important Topics for Class 9 Science Chapter 9 Force and Laws of Motion

Force can be used to change the magnitude of velocity of an object (that is, to make the object move faster or slower) or to change its direction of motion. It is an external agent that can potentially change the state of rest or motion of any body.

Balanced and Unbalanced Forces

Balanced force can be expressed as two magnitudes, typically equally, with opposite directional forces acting on a body. Unbalanced forces occurs when two forces are seen to act in opposite directions on a body and aren’t equal in either magnitude or in size.

Example of Balanced Force: When a vehicle is pushed with equal force from either sides, it will keep remaining at a resting state.
Example of Unbalanced Force: The movement of a seesaw.

Laws of Motion

Newton’s laws of motion are the fundamental building blocks of classical mechanics. Motion can be defined as the change in position of a body on basis of its surroundings in a respective time interval.

Example: What are the Newton’s laws of Motion?

Solution: Newton’s laws of Motion are:

First Law of Motion claims that a body will not change its state of rest or motion, unless an external force acts on it.
Second Law of Motion claims that the greater the mass of the body, the greater will the required force in order to accelerate it.
The Third Law of Motion claims that for every action, there is an equal and opposite reaction.

Conservation Laws

The laws of conservation include but are not limited to conservation of mass, energy, linear momentum and angular momentum. Conservation laws are known to deal with the fundamental forces of nature.

Example: Give two primary examples of conservation of energy.

Solution: The two primary examples of conservation of energy are:

Electrical energy being converted into sound energy.
Mechanical energy being converted into electrical energy.

Also Read:

Chapter Related Links
Law of Inertia	Unit of Moment of Inertia	Effects of Force
First Law of Motion	Second Law of Motion	Third Law of Motion
Difference Between Force and Momentum	Difference Between Momentum and Inertia	Linear Momentum Formula
Mass and Momentum	Moment Of Force	Interaction of Forces & Effects of Force Interaction
Inertia	Unit of Mass

Read More:

Important Science Study Guides
Named Reactions	Physics Constants	Difference between in biology
Difference between in chemistry	Difference between in physics	Periodic Table

CBSE X Related Questions

1.
Assertion (A): Reflex actions do not involve thinking.
Reason (R): Most reflex actions are controlled by the spinal cord.
- Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- Assertion (A) is true, but Reason (R) is false.
- Assertion (A) is false, but Reason (R) is true.
View Solution
2.
Identify the type of reproduction shown in the diagram given below:
- Budding
- Fragmentation
- Spore Formation
- Binary Fission
View Solution
3.
From the given situations, identify 'Chemotropic' and 'Geotropic' movements in parts of plants, respectively:
(i) Growth of pollen tube towards ovule.
(ii) Movement of sunflower towards sunlight.
(iii) Movement of root towards Earth/Gravity.
(iv) Movement of leaves due to breeze.
- (i) and (iii) respectively
- (iii) and (i) respectively
- (i), (ii) and (iii), (iv) respectively
- (i), (iii) and (ii), (iv) respectively
View Solution
4.
State two differences between the act of chewing food and salivation on sight of food.
View Solution
5.
Briefly mention the steps in double-circulation through human heart.
View Solution
6.
In human beings, the implantation of fertilised egg takes place in which part of female reproductive system?
- Oviduct
- Cervix
- Uterus
- Vagina
View Solution