While mass measures, how much matter is present in an object. Weight measures how strongly an object is pulled due to gravity. These two terms are often encountered by us in our day to day life. Whenever we discuss the weight of the body, we actually talk about its mass, but these two are not synonyms, in fact, these two are different notions.
Due to the lack of knowledge people use the two interchangeably, which is incorrect, as mass is the fundamental property of matter whereas weight is the force, generated out of gravitational pull on the object. So, read the entire article carefully, in which we’ve simplified the difference between mass and weight in detail.
Content: Mass Vs Weight
Comparison Chart
| Basis for Comparison | Mass | Weight |
|---|---|---|
| Meaning | Mass refers to the quantity of matter contained in a body. | Weight implies the force acted upon the object due to the pull of gravity. |
| What is it? | It is the measure of inertia. | It is the measure of force. |
| Location | It remains same, irrespective of the location. | It varies as per the location. |
| Physical Quantity | Scalar Quantity | Vector Quantity |
| Zero | It can never be zero. | When no gravity acts upon the body, it can be zero. |
| SI unit | Kilogram | Newtons |
| Measurement | Ordinary balance is used in measurement. | Spring balance is used in measurement. |
Definition of Mass
By the term ‘mass’ we mean, a physical quantity, which indicates the amount of substance or matter in something. It is the basic property of an object that gauges the object’s resistance to acceleration when force is exerted on it. Mass of an object tells about the total number, types and density of atoms contained in the object.
Mass is often measured by how much an object weighs, however, it is not weight because it remains same, irrespective of the location of the object. The internationally recognised unit of mass is kilogram (kg). However, there are also other units of measurements such as gram, milligram, tonnes or ounces and pounds. It is represented by M or m.
Definition of Weight
Weight implies the force caused by the gravitational pull of the earth, through which it attracts an object or body towards it. It is the product of mass (m) and acceleration of gravity (g), often represented by W. It is a vector quantity because it has both magnitude and direction, wherein the force acts vertically downwards. It is variable in nature, and that is why it increases or decreases with higher or lower gravity.
Further, the unit of weight is equal to the unit of force, because the weight of a particle is same as the force, that causes the particle to be pulled towards the earth’s centre. The weight of a physical body is directly related to its mass, in the sense that an increase in the mass, will result in the increase in its weight. In this way, weight is ultimately the measure of mass.
Key Differences Between Mass and Weight
The differences between mass and weight can be drawn clearly on the following grounds:
- The quantity of matter contained in a body is known as Mass. The force acted upon the object due to the pull of gravity, is called weight.
- Mass is defined as the measurement of inertia and inertia is the feature of a body that opposes, the change in its state. On the other hand, weight is the measurement of force; wherein force is the product of mass and acceleration due to gravity.
- While mass is the property of the object which remains same, throughout the universe. As against this, weight is that property of the substance that varies according to the location in the universe.
- Mass is a scalar expression that has magnitude only. Unlike weight is a vector measure, that has both magnitude and direction.
- Mass of an object can never be zero, whereas the weight of an object can be zero, if the gravitational force is not applied on the body, such as space.
- The unit of measurement of mass is kilogram (Kg), gram (g) and milligram (mg). Conversely, the measurement unit of weight is Newtons (N).
- The balance used in the measurement of mass is pan balance, lever balance, triple-beam balance and so on. On the contrary, spring balance or weighing machine are used to measure the weight.
Conclusion
There exist a direct relationship between the mass and weight, such that the greater the mass of something, the greater is its weight. Although, the main difference between the two terms lies in the fact that mass is constant, while the weight of an object changes as it depends on how far is the object from the centre of the earth.
S Sumanth says
Good explanation on mass &weight
Can you kindly reply the following :
1)when a mass of X kg is ejected from earth is ejected and reaches zero gravity how will it continue to move?
2)Whether will it be stationery in space?
3)will the mass so ejected in zero gravity of earth will be under gravity of say ,black holes?