KINEMATICS-1D
Kinematics in which we deal with the motion i.e. change in position with respect to a either fixed system or a
moving system (frame of reference) without taking into account of its cause or force.
For analysing motion of a particle, there are some physical quantities as its parameters
(i) Position or position vector - which is the location of the particle with respect to system of co-ordinate axes.
(ii) Displacement - the change in position vector.
(iii) Velocity - The time rate of change of displacement
(iv) Acceleration - The time rate of change of velocity.
PIYUSH SHUKLA
Motion (Translational)
Absolute Motion Relative Motion
(Frame of reference is (Frame of reference
a fixed body or system) is in motion)
t t + t
figure (i)
0 A B
x
x + x
uuur
In figure (i) motion is along positive x-direction AB = displacement in time t = xr
y
B (t + t)
r
B
r A(t)
A
x figure (ii)
O
r = r + r and rA= r
B
uuur uuur uuur r
In fig (ii) displacement in time t , AB OB OA r = change in position vector..
In any kind of motion, the magnitude of displacement is less than or equal to distance (actual path traversed).
AB S = Distance covered in time t .
uuur uur
AB Displacement is time t r or path length
S Dis tan cecovered
Average speed in time t =
t Time elapsed
uur A B
r Displacement
= Average velocity in time t = Time elapsed time t time t + t
t
If for different interval the particle has same average velocity then motion is said to be in uniform motion or
otherwise motion is said to be in non-uniform motion and if particle is in non-uniform motion then velocity at a
[1]
Kinematics in which we deal with the motion i.e. change in position with respect to a either fixed system or a
moving system (frame of reference) without taking into account of its cause or force.
For analysing motion of a particle, there are some physical quantities as its parameters
(i) Position or position vector - which is the location of the particle with respect to system of co-ordinate axes.
(ii) Displacement - the change in position vector.
(iii) Velocity - The time rate of change of displacement
(iv) Acceleration - The time rate of change of velocity.
PIYUSH SHUKLA
Motion (Translational)
Absolute Motion Relative Motion
(Frame of reference is (Frame of reference
a fixed body or system) is in motion)
t t + t
figure (i)
0 A B
x
x + x
uuur
In figure (i) motion is along positive x-direction AB = displacement in time t = xr
y
B (t + t)
r
B
r A(t)
A
x figure (ii)
O
r = r + r and rA= r
B
uuur uuur uuur r
In fig (ii) displacement in time t , AB OB OA r = change in position vector..
In any kind of motion, the magnitude of displacement is less than or equal to distance (actual path traversed).
AB S = Distance covered in time t .
uuur uur
AB Displacement is time t r or path length
S Dis tan cecovered
Average speed in time t =
t Time elapsed
uur A B
r Displacement
= Average velocity in time t = Time elapsed time t time t + t
t
If for different interval the particle has same average velocity then motion is said to be in uniform motion or
otherwise motion is said to be in non-uniform motion and if particle is in non-uniform motion then velocity at a
[1]
