Unit 4 UNIFORM CIRCULAR MOTION Definitions and Equation

Unit 4 UNIFORM CIRCULAR MOTION

Definitions and Equation

Example

Velocity and Acceleration What is the difference between speed and velocity? Therefore in circular motion if the speed isn’t changing what is ? What are three ways to cause acceleration? In circular motion the change an acceleration in direction causes

Centripetal Acceleration

Centripetal Acceleration The centripetal acceleration vector always points toward the center of the circle and continually changes direction as the object moves

Centripetal Acceleration

Example – Centripetal Acceleration

Example – Centripetal Acceleration

Example – Centripetal Acceleration

Demonstration of Centripetal Acceleration https: //www. youtube. com/watch? v=90 r. Fib. Lkt. F 4

Review 1. Which direction does the centripetal acceleration vector point? 2. What is period? 3. How do you find the distance the object covers in a circular path? 4. If the radius of the curve increases what happens to the centripetal acceleration?

Unit 4 Continued: Centripetal Force Newton’s Laws of motion apply to objects moving in a curved path. What does inertia say objects want to do? If an object is released from its circular path, it will continue in straight line tangent to the circle. How do we keep a body moving in a circle?

Centripetal Force Think about a rock or a ball on a string, how do you keep it whirling around? Keep the object in line by applying a force on the string. http: //www. pbslearningmedia. org/asset/lsps 07_int_circmo tion/

Centripetal Force The force is called the centripetal force. Centripetal force is the center seeking force Causes the object to stay in the circular path Force is exerted toward the center of the circle If Force is removed then the object would move off tangent to the path

Examples of Centripetal Force Centripetal force isn’t a new kind of force! The name just applies to any force that keeps something moving in a circle. Whirling an object on the end of a string The force is tension in the string. Planets orbiting the sun The force is gravity. A car turning a corner The force is the friction between the tires and the road.

To find Centripetal Force

Example 1 – Centripetal Force

Example 2 – Centripetal Force

Example 2 – Centripetal Force

Example 3 – Centripetal Force