class 9th physical // Chapter - Motion
| Chapter - Motion |
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| • Some representation 1. दूरी [ distance ] → s या d 2. विस्थापन [ displacement ] → s या d या x 3. समय [ time ] → t 4. प्रारम्भिक चाल / वेग [ initial velocity ] → u 5. अंतिम चाल / वेग [ Final velocity ] → v 6. त्वरण [ acceleration ] → a 7. वृत की त्रिज्या [ radius ] → r 8. कोणीय वेग [ angular velocity ] → w ( ओमेगा ) • Some Major Important Formulas   Some quantities and their S. I. unit 1. In the S. I. system the unit of distance is meter. 2. In the S. I. system the unit of velocity is meter / second. 3. In the S. I. system the unit of acceleration is meter / second. 4. In the S. I. system the unit of mass is kilogram. 5. In the S. I. system the unit of force is newton. 6. In the S. I. system the unit of angular velocity is radian/second. Note :- The initial velocity is zero in two cases: 1. When the object starts moving from rest. 2. When the object falls from top to bottom. ** • What is motion ? Answer :- Change in the position of the object is called motion . That is, when an object keeps changing its position in comparison to the objects around it, then the changing position of the object is called motion. # Motion Type : Motion are generally of the following types. 1. Linear motion 2. Circular motion 3. Oscillatory motion 4. Periodic motion |
