Mass is the amount of **matter** contained in a body. **Mass** of the body is the constant quantity and does not change with the change of position or location. Weight is the force **exerted** by a body when it is in a gravitational field. Weight of the body is the variable quantity and changes with the change in position and location due to the acceleration of the **gravity** acting on it.

Mass is a **constant** for each object, meaning that the mass won't change unless the object changes. It is an abstract property of the body invariant of the support and defining what **acceleration** the body gets when being affected by a force. On the other hand Weight changes due to the **gravity** ; any object's weight is the force pulling it down to the ground.

Newton's law:

### F=MA

Where F is the **force** , M is the **mass** and A is the **acceleration** (the gravity in case of weight). So W=MG, where W is the **weight** , M is the **mass** and G is the **gravity** . So if you apply a force of 1 Newton to a mass of 1kg it will accelerate at 1m/s** ^{2}**. This is true whether the object is floating in space or in a gravity field. This is why weightlessness is possible inside an airplane in freefall (or a space ship rotating an orbit) both experience the same

**acceleration**and so both move with the same speed and so the body exerts zero force onto its support and so it becomes

**weightless**.

## Mass

- Independent of Gravity.
- Can never be zero.
- Scalar and base quantity.
- Ordinary balance is used in measurement.
- Measured in grams and kilograms.
- Resists motion.

## Weight

- Dependant of Gravity.
- When no gravity acts upon the body, it can be zero.
- Vector and derived quantity.
- Measured using a spring balance.
- Expressed in Newton (N).
- Produce motion.

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