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Centre of mass

Centre of mass of an object can be said as the point of mass where it has the average weight of its overall mass or says net mass is zero. All the aspects of the centre of mass are explained in the given centre of mass study material.

In a nutshell, a Central point of any mass where its net mass is near zero is called the centre of mass of an object. The centre of mass relies on two factors, namely masses and the object’s location. Moreover, the centre of mass for tough and rigid objects tends to differ from those with loose ends. In order to find the centre of mass, the addition of multiplication of masses with their corresponding vectors is divided by the total mass of both objects. However, the concept is broad, though here’s a curated and complete centre of mass study material.

What is the centre of mass?

The centre of mass of anybody is defined as the point where all the net mass of an object or a body appears to be focused or zero. It can be said that the focal point of mass (or centre of mass) of any item or body lies in itself. The centre of mass depends on two factors, masses of objects and their positions. Based on these, one can easily measure the centre of mass.

The idea of the centre of mass was first presented by the antiquated Greek mathematician, physicist, and architect Archimedes of Syracuse. Issac Newton utilised this concept theory to prove his inverse square gravitation law.

Centre of mass of objects

For tough or rigid objects, the centre of mass of any solid body or object is irremovable in reference to the objects.

For loose ending objects like a bullet that just shot from the shotgun, the centre of mass is in the space (or space), so in some cases, we can say that centre of mass is not fixed with positions.

Examples

We can understand this term by taking one or two simple examples- 

  • A playing ball has a centre of mass just in the middle of its location. 

  • In rectangles, the junction of the two diagonal lines is where a rectangle’s centre of mass is located.

Let’s take a look at another “moving example” of the centre of mass – 

  • Whenever a dancer raises her arms, her centre of mass moves higher in her body as to when her arms are at her sides.

Centre of mass formula 

The centre of mass is the multiplication of total system masses with their positioned vectors is equal to the addition of object masses and their respective position vectors. The centre of mass is defined as R(COM).

Suppose there are two objects of masses, M1 and M2

Then the R1 & R2 are their position vectors.

So, according to the above terminology, the Centre of masses of positioned vector, R(COM) is calculated as:

[M1 + M2] * R (COM) = M1R1 + M2R2

R (COM) = [M1R1+ M2R2][M1 + M2]

Motion of Centre of mass

The centre-of-mass (COM) is a key component of motion that describes an object’s motion when reduced to a point mass. An applied net force results in a translational motion of the COM. By applying total combined force to another part of the body, the entity will move and spin about its COM.

Applications

The centre of mass of an aircraft is a critical position that considerably impacts the aircraft’s equilibrium. The centre of mass must lie within certain limits in order for the aircraft to be secure enough to fly safely.

Determining the centre of mass’s position is significant since it enables you to assess dynamical problems based on the centre of mass’s motion. When a hammer is thrown into the air, its centre of mass will travel along a curved path. It’s as if a particle had been flung into the air.

Conclusion

We came through all the crucial aspects of the centre of mass from all the above. We learned the centre of mass objects, their formula and applications alongside all general information. The centre of mass of an object is a point at which the net mass of an object is focused or zero. Moreover, we came through the formula of the centre of mass which can be used to determine the point of mass where it has zero or focused net mass. Also, the position centre of mass of objects varies by object’s characteristics. It is fixed in tough and rigid objects whereas moving in low ending objects. 

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Frequently asked questions

Get answers to the most common queries related to the NDA Examination Preparation.

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