# How do our bodies change our mass?

## Mass and Force in Physics

### The concept of force in physics

One can only recognize forces by their effects. You can deform bodies, accelerate bodies, slow down bodies and change the direction of movement of bodies. Forces have size, direction and point of application. They are represented by arrows (force vectors), see vector calculation.

### Definition of weight in physics

Weight is the force with which a body is attracted to the earth. It is location-dependent.

### Units of measure for the Weight force

The unit of measurement of force is the newton (N).
e.g. F = 10 N or F = 0.2 N or F = 100 N

### The concept of Dimensions in physics

Every body has a mass. This is expressed in “being heavy” and “being sluggish”. However, the mass of a body does not depend on the location. However, it can be determined by comparing the masses on the scales.

### Units of measure for the mass

The unit of measurement for mass is the kilogram (kg).
e.g. m = 10 kg or m = 100 g or m = 10 mg

### Newton's law of force

Question:
Who starts faster, a moped or a truck?
What does the magnitude of the acceleration depend on?

The engine power and mass determine the acceleration.

### attempt

We accelerate a mass m with different forces.

Result:

If the mass remains constant, then the force is variable.
The greater the force, the greater the acceleration.
In other words: the acceleration is proportional to the force.

### attempt

We accelerate masses of different sizes with the same force.

Result:

If the force remains constant, then the mass is variable.
The larger the mass, the smaller the acceleration.
In other words: the acceleration is inversely proportional to the mass.

Force, mass and acceleration are interdependent.

### Formula acceleration = force / mass

a = F / m
A precise check can be carried out with a series of measurements on the roadway.

### Newton's law of force

It is also called the dynamic constitution.

### Galileo Galilei's Theorem of Inertia

A body remains at rest or in uniform motion when there is no force acting on it.
In other words:
A body can only change its state of motion under the influence of a force.

Question:
Why does a car that is driven at full throttle only reach a certain top speed?

### Formula acceleration force = driving force - friction force

F.b = Fa - Fr
When the frictional force Fr is exactly as great as the driving force Fa, then the speed no longer increases.

### Definition of the unit of force 1 Newton

The force 1 N acts when a body with a mass of 1 kg has an acceleration of 1 m / s2 is granted.

You need these formulas, for example, for the Acceleration measurement on the road.

Here you will find an overview of further contributions on the subject of mechanics,it also contains links to tasks.

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