UNIT 3: Motion

Chapter 5: Investigating Motion

Chapter 6: Applied Motion

Chapter 6: Applied Motion

UNIT 3 Chapter 6: Applied Motion

TO PREVIOUS SLIDE

When you think about velocity changes, you might think about fast- moving race cars, but velocity changes do not have to involve high speeds. The person climbing the waterfall experiences velocity changes, but those changes involve slow speeds.

•What are some other examples of velocity changes?

What do you think the driver of this race car is feeling as the car goes faster and faster?

6.1 Changes in Velocity

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• When a car is moving at constant speed—uniform motion—you are almost unaware of any motion at all.

• When you travel in a car that has changing speed, your body feels some of the changes.

Acceleration

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• Acceleration, is a change in the velocity of an object during a time interval or a rate of change of velocity per unit of time.

• Acceleration can be a change in speed or a change in direction of the object.

• Acceleration is a vector quantity.

Describe two situations in which you are accelerating when you are riding a bicycle.

Graphing Accelerated Motion

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• When an object has accelerated motion, the motion is not uniform.

• Position-time graphs of accelerated motion are always curved.

• Describe the changes in speed in each graph.

Continued…

Graphing Accelerated Motion

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• The slope of the line in the position-time graph (A) shows that the velocity is constant.

• The slope of the velocity-time graph (B) indicates that the velocity is constant; therefore, acceleration is also constant.

Continued…

What does the zero slope of the velocity-time graph indicate about the acceleration of the object?

Graphing Accelerated Motion

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• The curve of the position-time graph (A) indicates that the velocity is increasing.

• The slope of the velocity-time graph (B) indicates that velocity is increasing and is constant.

Continued…

What does the slope of the velocity-time graph indicate about the acceleration of the object?

What does the slope of the velocity-time graph indicate about the acceleration of the object?

Graphing Accelerated MotionUNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• The curve of the position-time graph (A) indicates that the velocity is decreasing.

• The slope of the velocity-time graph (B) indicates that velocity is decreasing and is constant.

Which two standard shapes make up the area under this velocity-time graph?

Calculating Displacement Graphically

UNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• The displacement of an object from time, t1, to time, t2, is equal to the area under the velocity-time graph during the defined time interval.

• When the area under a velocity-time graph is complicated, you can divide the area into standard-size pieces and find the sum of the area of all the pieces.

Motion in a CarUNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

When you ride in a vehicle, such as a car, train, truck, or airplane, you feel the effects of acceleration on your body.

Describe the effects of acceleration on the crash dummy when the vehicle comes to a sudden stop.

Section 6.1 ReviewUNIT 3 Chapter 6: Applied Motion Section 6.1

TO PREVIOUS SLIDE

• A change in the velocity of an object during a time interval is acceleration.

• The change in velocity can be a change in the speed of the object, a change in the direction of the object, or both a change in speed and direction of an object.

• Analyzing a position-time graph gives you information about the velocity of the object.

• Analyzing a velocity-time graph gives you information about the acceleration of the object.

• During car rides, you experience zero acceleration, positive acceleration, and negative acceleration.

6.2 Using Motion FormulasUNIT 3 Chapter 6: Applied Motion Section 6.2

TO PREVIOUS SLIDE

The distance and displacement of an object usually have different magnitudes.

Why are the displacementand the distance travelleddifferent for the trip fromAnnapolis Royal to Amherst?

Calculating Speed and VelocityUNIT 3 Chapter 6: Applied Motion Section 6.2

TO PREVIOUS SLIDE

The speed and velocity of an object can be calculated using the formulas below.

What is the key difference between these two formulas?

Calculating AccelerationUNIT 3 Chapter 6: Applied Motion Section 6.2

TO PREVIOUS SLIDE

The acceleration of an object can be calculated using the formula below.

What is the direction of acceleration of the object?

Section 6.2 Review

UNIT 3 Chapter 6: Applied Motion Section 6.2

TO PREVIOUS SLIDE

• Formulas are used to mathematically calculate speeds, velocities, distances, and displacements.