# Uniform Motion

## Introduction

A motion at a constant speed is called uniform motion.

## Experiment

A car moves at a constant speed on a straight path. At certain points travel time and traveled distance are measured and recorded.

ResetStart

 $$s$$ in $$\rm m$$ $$t$$ in $$\rm s$$ $$v$$ in $$\rm \frac{m}{s}$$

## Results

The distance-time curve is a straight line passing through the origin. This shows that the way and the time are proportional to each other.

The proportionality constant is obviously the velocity $$v$$ of the body.

$$v = \dfrac{s}{t}$$

The speed-time curve is a straight line parallel to the X axis. This shows that the velocity remains the same throughout the journey. The following applies:

$$v = \text{const.}$$

## Units of velocity

To specify the velocity the units $$\rm \frac{m}{s}$$ and $$\rm \frac{km}{h}$$ are often used. They can be converted into each other as follows:

$$\rm 1 \,\, \dfrac{km}{h} = \dfrac{1000 \,\, m}{3600 \,\, s} = \dfrac{5}{18} \dfrac{m}{s}$$
$$\rm 1 \,\, \dfrac{m}{s} = \dfrac{0,001 \,\, km}{\frac{1}{3600} \,\, h} = \dfrac{0,001 \cdot 3600}{1} \dfrac{km}{h} = 3,6 \,\, \dfrac{km}{h}$$

### Sources

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