Kinematics Notes - Class 11 PDF Download

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KINEMATICS 
1. The branch of physics that deals with the motion of a body due to the application of force is called 
mechanics. 
2. Mechanics is divided into two branches namely dynamics and statics. 
3. The branch of mechanics that deals with the state of rest of a body is called statics. 
4. The branch of mechanics that deals with the state of motion of a body is called dynamics. 
5. Dynamics is classified into kinematics and kinetics. 
6. Kinematics is the study of motion which relates to the motion of bodies without reference to either 
the mass or the force causing it. 
7. Kinetics is the study of motion which relates to the action of forces causing the motion and the 
mass that is moved. 
8. A body is said to be at rest if its position remains constant with respect to its surroundings or frame 
of reference. 
9. A body is said to be in motion if its position is changing with respect to its surroundings or frame 
of reference. 
10. The line joining the successive positions of a moving body is called its path. The length of the 
path gives the distance travelled by the body. 
11. Displacement is the directed line segment joining the initial and final positions of a moving body. 
It is a vector. 
12. If every particle of a moving body traverses the same distance along parallel paths, which may be 
straight or curved, while the body is moving, then the motion of the body is called translatory 
motion. 
13. When the path traversed by each particle of a body is a straight line, then its motion is said to be 
rectilinear. 
14. When the path traversed by the particles are parallel paths, then the motion is said to be 
curvilinear. 
SPEED : 
15. Speed of a body is the rate at which it describes its path. Its SI unit is ms
-1
. 
16. Speed is a scalar quantity. 
17. Speed =
taken time
travelled distance
. 
18. A body is said to be moving with uniform speed if it has equal distances in equal intervals of time, 
however small these intervals may be. 
19. A body is said to be moving with non uniform speed if it has unequal distances in equal intervals 
of time or equal distances in unequal intervals of time, however small these intervals may be. 
20. Average speed =
taken time total
travelled distance total
 
21. Instantaneous speed =
dt
ds
t
s
Lt
0 t
=
?
?
? ?
.