C H A P T E R

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C H A P T E R   2Kinematics in One Dimension
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Mechanics
The study of Physics begins with mechanics.
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Mechanics
The study of Physics begins with mechanics.
Mechanics is the branch of physics that focuses
on the motion of objects and the forces that
cause the motion to change.
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Mechanics
The study of Physics begins with mechanics.
Mechanics is the branch of physics that focuses
on the motion of objects and the forces that
cause the motion to change. There are two parts
to mechanics Kinematics and Dynamics.
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Mechanics
The study of Physics begins with mechanics.
Mechanics is the branch of physics that focuses
on the motion of objects and the forces that
cause the motion to change. There are two parts
to mechanics Kinematics and Dynamics.
Kinematics deals with the concepts that are
needed to describe motion, without any reference
to forces. Chapter 2 Kinematics in one
dimension Chapter 3 Kinematics in two dimensions
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Mechanics
The study of Physics begins with mechanics.
Mechanics is the branch of physics that focuses
on the motion of objects and the forces that
cause the motion to change. There are two parts
to mechanics Kinematics and Dynamics.
Kinematics deals with the concepts that are
needed to describe motion, without any reference
to forces. Chapter 2 Kinematics in one
dimension Chapter 3 Kinematics in two
dimensions Dynamics deals with the effect that
forces have on motion. Chapter 4 Dynamics
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Distance and Displacement
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Distance and Displacement
Starting from origin, O a person walks 90-m east,
then turns around and walks 40-m west.
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Distance and Displacement
Starting from origin, O a person walks 90-m east,
then turns around and walks 40-m west.
Q What is the total walked distance?
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Distance and Displacement
Starting from origin, O a person walks 90-m east,
then turns around and walks 40-m west.
Q What is the total walked distance? A 130-m
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Distance and Displacement
Starting from origin, O a person walks 90-m east,
then turns around and walks 40-m west.
Q What is the total walked distance? A 130-m Q
What is the displacement?
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Distance and Displacement
Starting from origin, O a person walks 90-m east,
then turns around and walks 40-m west.
Q What is the total walked distance? A 130-m Q
What is the displacement? A 50-m, due east.
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Displacement
The displacement ?x is a vector that points from
the initial position to the final position. SI
Unit of Displacement meter (m)
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2.2 Speed and Velocity

• Average Speed
• Average Velocity
• Instantaneous Velocity
• Instantaneous Speed

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Average Speed
Units for speed m/s, MPH, kmPH.
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Average Velocity
Units for velocity m/s, MPH, kmPH.
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Instantaneous Velocity and Speed
The instantaneous velocity v indicates how fast
an object moves and the direction of the motion
at each instant of time.
The magnitude of the instantaneous velocity is
called the instantaneous speed, and it is the
number (with units) indicated by the speedometer.

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Acceleration
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Acceleration
Units m/s2, cm/s2
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Instantaneous acceleration
Acceleration at a particular instant is called
instantaneous acceleration.
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Deceleration
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Deceleration
An object speeds up when the acceleration and
velocity vectors point in the same direction.
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Deceleration
An object speeds up when the acceleration and
velocity vectors point in the same direction.
Whenever the acceleration and velocity vectors
have opposite directions, the object slows down
and is said to be decelerating.
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Deceleration
An object speeds up when the acceleration and
velocity vectors point in the same direction.
Whenever the acceleration and velocity vectors
have opposite directions, the object slows down
and is said to be decelerating. Example 4 A
drag racer crosses the finish line, and the
driver deploys a parachute and applies the brakes
to slow down. The driver begins slowing down when
t0 9.0 s and the car's velocity is v0 28
m/s. When t 12.0 s, the velocity has been
reduced to v 13 m/s. What is the average
acceleration of the dragster?
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Kinematics Equations