FisDas1 kinematika1d a

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Kinematics

is

the

science of describing

the motion of objects

using words, diagrams,

numbers, graphs, and

equations.

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The

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Lesson 1

Describing Motion with Words

• Distance

• Displacement

• Speed

• Velocity

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Distance and Displacement

 Distance is a scalar quantity which refers to "how much ground an object has covered" during its motion.

 Displacement is a vector quantity which refers to

"how far out of place an object is"; it is the object's change in position.

A physics teacher walks 4 meters East, 2 meters South, 4 meters West, and finally 2 meters North.

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Speed and

Velocity



Speed

Speed is a scalar quantity which refers to "how fast an object is moving." A fast-moving object has a high speed while a slow-moving object has a low speed. An object with no movement at all has a zero speed



Velocity

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Speed and

Velocity

Instantaneous Speed - speed at any given instant in time. Average Speed - average of all instantaneous speeds;

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Lesson 2 focuses on the use of

diagrams to describe motion. The two

most commonly used types of

diagrams used to describe the motion

of objects are:



ticker tape diagrams



vector diagrams

Lesson 2

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The distance between dots on a ticker tape represents the object's position change during that time interval. A large distance between dots indicates that the object was moving fast during that time interval. A small distance between dots means the object was moving slow during that time interval.

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Ticker Tape Diagrams

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Ticker Tape

Diagrams

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Vector Diagrams

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Vector Diagrams

In a vector diagram, the magnitude of a vector is represented by the size of the vector arrow. If the size of the arrow in each consecutive frame of the vector diagram is the same, then the magnitude of that vector is constant.

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Describing Motion with Position vs. Time

Graphs

The Meaning of Shape for a p-t

Graph

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Describing Motion with Position vs. Time

Graphs

Now consider a car moving with a rightward (+), changing velocity - that is, a car that is moving rightward but speeding up or

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Describing Motion with Position vs. Time

Graphs

Now consider a car moving at a constant velocity of +5 m/s for 5 seconds, abruptly

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Describing Motion with Position vs. Time

Graphs

Determining the Slope on a p-t

Graph

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The Meaning of Slope for a v-t Graph

Consider a car moving with a constant velocity of +10 m/s. A car moving with a constant

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The Meaning of Slope for a v-t

Graph

_{Now consider a car moving with a changing}

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The Meaning of Slope for a v-t

Graph

From 0 s to 4 s: slope = 0 m/s2

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Lesson 4 : Describing Motion with Velocity vs. Time Graphs

The Meaning of Shape for a v-t Graph

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Lesson 4 : Describing Motion with Velocity vs. Time Graphs

Now consider a car moving with a rightward (+), changing velocity - that is, a car that is moving rightward but speeding up or accelerating. Since the car is moving in the positive direction and speeding up, the car is said to have a positive

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Determining the Slope on a v-t

Graph

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Lesson 4 : Describing Motion

with Velocity vs. Time

Graphs



The Meaning of Shape for a v-t

Graph



The Meaning of Slope for a v-t

Graph



Relating the Shape to the Motion



Determining the Slope on a v-t

Graph



Determining the Area on a v-t

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Lesson 4 : Describing Motion

with Velocity vs. Time Graphs

The velocity vs. time graphs for the two types of motion - constant velocity and changing

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