What is the Newton's Third Law? What is the formula of Newton's Third Law? When do students in Vietnam study the Newton's Third Law?

What is the Newton's Third Law? What is the formula of Newton's Third Law?

Newton's Third Law is one of the fundamental principles of physics, helping us better understand the interactions between objects in the universe. Mastering this law will help you solve many physics problems and gain deeper insights into the world around us.

*Newton's Third Law: Interaction between objects

Newton's Third Law is one of the fundamental laws of physics, describing the interaction between objects. This law states that:

In every case, when object A exerts a force on object B, object B also exerts a force on object A. These two forces are equal in magnitude but opposite in direction.

*Formula:

F$_{AB}$ = - F$_{BA}$

*Where:

F$_{AB}$: The force object A exerts on object B

F$_{BA}$: The force object B exerts on object A

The "-" sign indicates that these two forces are opposite in direction.

*Example:

Kicking a ball: When you kick a ball, your foot exerts a force on the ball (F$_{foot-ball}$). At the same time, the ball exerts an equal force in the opposite direction on your foot (F$_{ball-foot}$).

Walking: When you walk, your foot exerts force on the ground. In response, the ground exerts a force on your foot, pushing you forward.

Interaction between the Earth and the Sun: The Earth attracts the Sun with a gravitational force, and the Sun also attracts the Earth with a force of equal magnitude but in the opposite direction.

*Note: Information about Newton's Third Law including the formula and examples is for reference only./.

What is the Newton's Third Law? What is the formula of Newton's Third Law? When do students in Vietnam study the Newton's Third Law?​ (Image from the Internet)

When do students in Vietnam study the Newton's Third Law?​

Based on Section 5 of the General Education Program of the Physics subject issued with Circular 32/2018/TT-BGDDT, the requirements for grade 10 Physics are as follows:

*Dynamics

The three Newtonian laws of motion:

- Conduct experiments, or use given data to extract a ~ F, a ~ 1/m, from which to derive the expression a = F/m or F = ma (Newton's Second Law).

- From the results obtained (from experiments or using given data), or reasoning based on a = F/m, it is stated that mass is the quantity that characterizes an object's inertia.

- State Newton's First Law and illustrate with specific examples.

- Apply the relationship of derived units with 7 basic units of the SI system.

- State that the gravitational force acting on an object is the attractive force between the Earth and the object; the center of gravity of an object is the point where the gravitational force acts on the object; the weight of an object is the product of its mass and free fall acceleration.

- Describe with practical examples about equal and unequal forces.

- Qualitatively describe the falling motion in a uniform gravitational field when there is air resistance.

- Conduct a project or research topic on the increase or decrease of air resistance depending on the shape of the object.

- State Newton's Third Law and illustrate with specific examples; apply Newton's Third Law in some simple cases.

Thus, according to the above regulations, Newton's Third Law is taught in grade 10.

What are topics of the grade 10 Physics program in Vietnam?

Based on Section 5 of the General Education Program of the Physics subject issued with Circular 32/2018/TT-BGDDT, the topics of the grade 10 Physics program in Vietnam are as follows:

Topic 10.1. Physics in various professions

Overview of the development of physics:

- Discuss, propose, select, and execute Learning Tasks to:

+ Provide a brief overview of the birth and initial achievements of experimental physics.

+ Provide a brief overview of the role of Newtonian mechanics in the development of Physics.

+ List some major branches of classical physics research.

+ State the crisis in physics at the end of the 19th century, the premise for the birth of modern physics.

+ List some main fields of modern physics.

Introduction to research fields in physics:

- State the research object; list some simple theoretical models, some experimental methods of some major fields of modern physics.

- Discuss, propose, select, and perform Learning Tasks to learn about science models and theories that have been developed and applied to improve current technologies as well as develop new technologies.

Introduction to applications of physics in various professions:

- Describe practical examples of using physics knowledge in various fields (Military; Nuclear Industry; Meteorology; Agriculture, Forestry; Finance; Electronics; Mechanics, automation; Information, Communication; Scientific Research).

Topic 10.2. Earth and the Sky

Determine orientation:

- Identify the positions of star constellations: Ursa Major, Ursa Minor, Cassiopeia on a star map (or using practical tools).

- Determine the position of the North Star on the starry sky.

Visible motion characteristics of some celestial bodies on the starry sky:

- Use a solar system model, discuss to state some basic characteristics of the visible motion of the Sun, Moon, Venus, and Mercury on the starry sky.

- Use Copernican heliocentric model to explain some observable characteristics of the Sun, Moon, Venus, and Mercury on the starry sky.

Some astronomical phenomena:

- Use images (or multimedia documents), discuss to briefly and qualitatively explain phenomena: solar eclipse, lunar eclipse, tides.

Topic 10.3. Physics and Environmental Education

The necessity of environmental protection:

- Discuss, propose, select, and perform Learning Tasks to find out:

+ The necessity of environmental protection in the development strategy of nations.

+ The role of individuals and communities in environmental protection.

Physics with environmental education:

- Discuss, propose, select, and perform Learning Tasks to find out:

+ The impact of current energy use on the environment, economy, and climate of Vietnam.

+ An overview of pollutants in fossil fuels, acid rain, nuclear energy, ozone layer depletion, climate change.

- Discuss, propose, select, and perform Learning Tasks to find out:

+ Classification of fossil and renewable energy.

+ The role of renewable energy.

+ Some basic technologies to obtain renewable energy.