# Physics Tutorial 6.3 - Newton's Second Law for System of Particles Revision Notes

[ No Votes ]

In addition to the revision notes for Newton's Second Law for System of Particles on this page, you can also access the following Centre of Mass and Linear Momentum learning resources for Newton's Second Law for System of Particles

Centre of Mass and Linear Momentum Learning Material
Tutorial IDTitleTutorialVideo
Tutorial
Revision
Notes
Revision
Questions
6.2Newton's Second Law for System of Particles

In these revision notes for Newton's Second Law for System of Particles, we cover the following key points:

• The definition of particles in physics
• The role of centre of mass in the dynamics of a system of particles
• How to write the Newton's Second Law of Motion for a system of particles
• How to make use of the help of coordinates to study the movement of a system of particles

## Newton's Second Law for System of Particles Revision Notes

In physics, particles are objects whose dimensions are very small compared to their motion. Therefore, we do not consider the shape of particles at all during the calculation process and as a result, the study of their centre of mass gives the same result as the study of the entire system of particles.

All objects move because of the action of any force. Therefore, if there is any motion of a certain object, there is a force acting on the object as well. Thus, when a system moves, we can apply the Newton's Second law of Motion, which outlines the relationship between acceleration, acting force and mass of an object.

The same thing can be said for a system of particles as well. We must only replace the mass of a single object by the mass of the entire system and the force acting on a single object (or better, the resultant force) with the resultant force acting on all particles of the system. Then, the equation

asys = FR(sys)/msys

is used to determine the acceleration of the entire system.

The extended Equation of the Newton's Second Law of Motion for a system of particles is

asys = FR1 + FR2 + FR3 + …/m1 + m2 + m3 + …

where 1, 2, 3, are the indexes for the objects included in the system.

When written in coordinates, the above equation (which is in vector form), splits in two (or three) similar equations written for each dimension separately:

ax(sys) = FRx(sys)/msys

and

ay(sys) = FRy(sys)/msys

Then, we can use the Pythagorean Theorem to determine the magnitude of acceleration for this system of particles.

asys = √a2x(sys) + a2y(sys)

## Whats next?

Enjoy the "Newton's Second Law for System of Particles" revision notes? People who liked the "Newton's Second Law for System of Particles" revision notes found the following resources useful:

1. Revision Notes Feedback. Helps other - Leave a rating for this revision notes (see below)
2. Centre of Mass and Linear Momentum Physics tutorial: Newton's Second Law for System of Particles. Read the Newton's Second Law for System of Particles physics tutorial and build your physics knowledge of Centre of Mass and Linear Momentum
3. Centre of Mass and Linear Momentum Practice Questions: Newton's Second Law for System of Particles. Test and improve your knowledge of Newton's Second Law for System of Particles with example questins and answers
4. Check your calculations for Centre of Mass and Linear Momentum questions with our excellent Centre of Mass and Linear Momentum calculators which contain full equations and calculations clearly displayed line by line. See the Centre of Mass and Linear Momentum Calculators by iCalculator™ below.
5. Continuing learning centre of mass and linear momentum - read our next physics tutorial: Moment of Force. Conditions of Equilibrium

## Help others Learning Physics just like you

[ No Votes ]

We hope you found this Physics tutorial "Newton's Second Law for System of Particles" useful. If you did it would be great if you could spare the time to rate this physics tutorial (simply click on the number of stars that match your assessment of this physics learning aide) and/or share on social media, this helps us identify popular tutorials and calculators and expand our free learning resources to support our users around the world have free access to expand their knowledge of physics and other disciplines.