### Theory:

Mass is the quantity of matter contained in a body.

Mass is a basic property of matter. The mass of each substance is in solid, liquid or gaseous state.

**The following are the key points to know about mass:**

**1.**All the matter contains mass, that is why it is known as the base quantity.

**2.**Mass is

**scalar**quantity, that is mass only has

**numerical value**.

**3.**The mass of an object is a constant value and it does not vary by the changes of gravity, place, temperature or pressure.

**4.**The

**SI unit of mass**is

**kilogram**.

In the International System of Units, the basic unit of mass is the kilogram (kg).

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**kilogram**\(= 1000\)**gram**\(1\)

**gram**\(= 1000\)**mg**\(1\)

**ton**\(= 1000\)**kg****In our daily life, we did not use the word mass.**

For example, we would not ask what is your mass? But we would ask what is your weight?

So what is the difference between the mass and weight? Now let's see the difference between them.

S.No | Differentiating property | Mass | Weight |

1 | What is it? | Mass is the quantity of matter contained in a body. | The weight of an object is relevant to the force acting on the object. The force can be either gravity or to a reaction force that holds it in place. |

2 | Is it changeable? | The mass of an object is a constant value and it does not vary by the changes of gravity, place. | Weight has the capability to change place to place. |

3 | Quantity | The mass is the fundamental quantity. | The weight is the derived quantity. |

4 | Scalar/Vector | The mass is the scalar quantity | Weight is the vector quantity |

5 | How can you measure it | The mass is measured by the physical balance instrument. | Weight is measured using spring balance instrument |

6 | Unit | Kilogram | Newton |

**Mass measuring methods:**

We know that the SI unit of mass is kilogram, in our day to day life we generally use the term ‘weight’ that is actually mean the ‘mass’. Many things are measured in terms of ‘mass’ in the commercial world.

Using the below instruments we can determine the mass of an objects: