# What is the difference between mass and weight?

Mass and weight are two commonly used terms in Physics. In the beginning, most of the students think that mass and weight are synonyms of each other. It is not a fact because mass and weight are two different terms because mass is known as the property of a body and weight is force acting on a body. In order to clearly understand the difference between mass and weight, we have to take an overview of different parameters.

## Difference between mass and weight

Mass and weight are different from each other on the basis of different parameters. Here, we compare these parameters one by one.

## Difference between definitions of mass and weight

Mass is known as the property of the matter and with the help of mass, we can easily measure the strength of the gravitational attraction of a body. On the other hand, weight is the amount of force that is acting on the body. This force can acts on a body either due to gravity or any kind of the reaction force.
Difference between their quantities

As we know that there are two types of physical quantities. First is the scalar quantity and the second is a vector quantity. There is also a clear difference between vector and scalar quantities. Mass of an object is a scalar quantity. Its reason is that to measure the mass of an object, we just need magnitude and unit. On the other hand, the weight of an object is a vector quantity because if we want to measure the weight of an object, we need its magnitude, unit and direction.
Difference between values of mass and weight
We can also observe a clear difference between the values of these two terms. The value of mass is the same at all the places because it doesn’t depend upon gravity. Therefore, we can say that the mass of an object can never be zero.
Conversely, weight of an object depends upon gravity. Therefore, it has different values in different places. For example, the weight of an object has two different values at Earth and Moon due to the difference in the values of gravity at Earth and Moon. On the other hand, the mass of an object remains the same on the Earth as well as on the Moon.
Different values at different locations
If we change the location of an object, we can’t see any kind of difference in the mass of an object. On the other hand, if we change the location of an object, we can see a definite difference in the weight of an object. If we going higher and higher, the value of gravity will decrease. As a result, the weight of an object also decreases. Conversely, if we are decreasing our altitude, the value of gravity will increase and we see a definite increase in the value of the weight of an object.
The difference between measuring instruments of mass and weight
It is a fact that if we are going to measure anything, we require a measuring instrument. In a similar way, either we are going to measure the mass of an object or weight of an object, we require measuring instruments. As mass and weight are two different terms, therefore, there require two different measuring instruments to measure these two terms. We can easily measure the mass of an object with the help of an ordinary balance. On the other hand, to measure the weight of an object, there requires spring balance.
Difference between their units
A standard for the measurement of an object is known as a unit. To measure the mass and weight of an object, we have to use two different units. The SI (System International) unit to measure the mass of an object is Kilogram and it is abbreviated as Kg. On the other hand, the SI (System International) unit to measure the weight of an object is Newton and it is abbreviated as N.
Difference between their formulas
In Physics, we can’t deny the importance of Mathematics because there require mathematical formulas to measure different terms. The formula to measure the mass of an object is given below;
F = ma                or             m = F/a
We can easily measure the mass of an object if we know the values of force and acceleration of this object. The formula to measure the weight of an object is also given below;
W = mg
We can easily measure the weight of an object if we know the values of mass and gravity of this object.
With the help of these formulas, it is also possible for us to convert the mass of an object into weight and vice versa. For example, if the mass of an object is 10Kg, we can convert it into weight in the following way;
W = 10*9.8 = 90.8N
External factors affecting mass and weight
As we know that mass is an intrinsic property of an object and that’s why there is no external factor that can affect the mass of an object. On the other hand, the weight of an object depends upon the mass of that object. Therefore, the force of attraction can easily influence the value of the weight of that object. That’s why if you are going to measure the quantity of an object, it is better for you to use mass rather than weight. Its reason is that the mass of an object remains the same at all the places, whereas, the weight of an object changes by changing the altitude.
Why we use mass in the formula to measure weight?
Most of the students think that due to lots of differences between mass and weight, why we are still using mass in the formula to measure weight. Its answer is that the weight of an object is due to the gravitational force that attracts a body. If the mass of an object is very small, the value of the gravitational force will also be small. That’s why we can observe that a fog particle remain suspended in the air. Due to this reason, it is necessary for us to use mass in the formula of the weight. Another reason is that mass is the functional property of the matter and weight is known as the consequence of that property.
To sum up, we can say that mass and weight depends on each other. Greater the value of the mass, greater will be its weight and vice versa. The main difference between two terms is that mass is a constant quantity, whereas, the weight of an object changes with the change in the altitude.
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