Best Solutions, Video Classes, Live Problem Classes, Worksheet, Test Exam Paper for CBSE Class 9 Science Chapter 8 Motion.
Class 9 Science Chapter 8 Motion
Uniform motion: When an object covers equal distances in equal intervals of time, it is said to be in uniform motion.
Non-uniform motion: Motions where objects cover unequal distances in equal intervals of time.
Speed: The distance travelled by an object in a unit of time is referred to as speed. Its unit is m/s.
Average speed: For non-uniform motion, the average speed of an object is obtained by dividing the total distance travelled by an object by the total time taken.
Velocity: Velocity is the speed of an object moving indefinite direction. S.I. unit is m/s.
Acceleration: Change in the velocity of an object per unit of time.
NCERT Class 9 Science Chapter 8 Motion (All intext and exercise questions solved)
1. An object has moved through a distance. Can it have zero displacement? If yes, support your answer with an example.
Solution: Yes, an object which has moved through a distance can have zero displacement if it comes back to its initial position.
Example: If a person jogs in a circular park which is circular and completes one round. His initial and final position is the same.
Hence, his displacement is zero.