Question

Explain with proper examples motion is relative.

Answer 1

Part 1. Motion:

1. A motion may be defined as the change of position of an object with respect to time.
2. When a book falls from the table, water flows in a river, windows rattle, etc all are examples of motion.
3. The air we breathe also exhibits motion.
4. Everything in the universe moves, and the universe is also in continual motion.
5. The following are different types of motion:

• Linear Motion.
• Rotary Motion.
• Oscillatory Motion.

Part 2. Motion is relative.

1. This concept of reference frames or fixed frames was introduced to discuss relative motion in one or more dimensions.
2. When we say an object is moving with a certain velocity, then that velocity is with respect to some frame known as the reference frame.
3. In our daily life, whenever we measure the velocity of an object, we take ground or earth as the reference frame.
4. For example, if you are traveling on a train and the train is moving at a speed of 100 km/hr.
5. Then your speed compared to another passenger sitting on that train is zero.
6. According to him, you are stationary. But if someone is looking from outside the train, standing on the ground.
7. Then he will say, you are moving with 100 km/hr as you are on the train and the train is moving with 100 km/hr.

Hence, the motion observed by someone depends on the location of that person. This type of motion is called relative motion. That's why we call motion relative.