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PUMPA - SMART LEARNING
எங்கள் ஆசிரியர்களுடன் 1-ஆன்-1 ஆலோசனை நேரத்தைப் பெறுங்கள். டாப்பர் ஆவதற்கு நாங்கள் பயிற்சி அளிப்போம்
Book Free DemoIn certain cases, motion is observed indirectly. For example, the movement of dust and leaves on a tree denotes the flow of air from one place to another; the wonderful phenomena of sunrise and sunset show the Earth's rotation, and the change of seasons every year shows the motion of the Earth around the Sun.
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Motion of the Earth around the Sun
While travelling on a train, the trees on the sides seem to be moving backwards. Have you ever noticed this? If so, do you think the same will apply to a person standing near the tree?
The answer will be, NO!
![Ashish_wassup6730 Shutterstock.jpg](https://resources.cdn.yaclass.in/0c86d28a-1113-4684-bca2-ac973a6e2162/Ashishwassup6730Shutterstockw300.jpg)
Moving trains
When we are sitting on a train that is actually at rest, sometimes it appears to move. As motion is relative, if the objects outside the train move, our eyes perceive it in a way that we are moving.
An object can appear to be moving for one person, while it seems to be stationary for another. Hence, motion is a relative phenomenon.
![shutterstock_688477798.jpg](https://resources.cdn.yaclass.in/e65ec26e-2164-4124-8cab-72a0660ee075/shutterstock688477798w300.jpg)
A moving bus
Now we know the motions are relative; then let us see the classifications of the motions.
S. No | Type of motion | What is it? | Example |
1. | Linear motion | The object moves along a straight line. | A car travelling in straight road. |
2. | Circular motion | The object travels in a circular path. | Movement of artificial satellite orbiting the earth. |
3. | Periodic or oscillatory motion | Objects that are in repeated motion for equal intervals of time. | The pendulum of a clock. |
Motions are complex sometimes. Objects may move in a straight line or a circle. Sometimes, it may rotate or even vibrate. In certain situations, it can be a combination of all of these.