Unit 2 Lesson 2 Acceleration Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 2 Lesson 2 Acceleration Indiana Standard Copyright © Houghton Mifflin Harcourt Publishing Company Demonstrate and describe how an object’s speed or direction of motion changes when a force acts upon it. Demonstrate and describe that an object’s speed and direction of motion remain unchanged if the net force acting upon it is zero.

Getting up to Speed Copyright © Houghton Mifflin Harcourt Publishing Company How do we measure changing velocity? Acceleration is the rate at which velocity changes. An object accelerates if its speed, direction, or both change. Acceleration depends on how much velocity changes and how much time that change takes. Unit 2 Lesson 2 Acceleration

How do we measure changing velocity? What is the change in velocity for each second of time that passes? Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Acceleration

How is average acceleration calculated? Average acceleration = (final velocity – starting velocity)/time a = (v 2 – v 1 )/t Acceleration is measured in meters per second squared (m/s 2 ). Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Acceleration

What a Drag! Copyright © Houghton Mifflin Harcourt Publishing Company How can accelerating objects change velocity? Acceleration refers to both increases and decreases in speed. A change in direction is also acceleration. An increase in velocity is called positive acceleration. A decrease in velocity is called negative acceleration. Unit 2 Lesson 2 Acceleration

How can accelerating objects change velocity? Is the horse showing negative acceleration or positive acceleration? Explain. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Acceleration

How can accelerating objects change velocity? An object traveling in a circular motion is always changing its direction, and so it always experiences acceleration. Centripetal acceleration is acceleration in a circular motion. Copyright © Houghton Mifflin Harcourt Publishing Company Unit 2 Lesson 2 Acceleration