2. 1. Title: Power of a Motor Power of a Motor 2. Date: Today’s Date 3. Names: Team members and cooperative jobs. Team members and cooperative jobs.

3. 4. Targets: 4. Targets: I can define work, power and force.

4. Work - Activity resulting when a force acts on an object that moves the object some distance. When work is done energy changes from one form to another.

5. Notes: Work: The product of a force multiplied by the distance over which that force is acted. Work: The product of a force multiplied by the distance over which that force is acted. Force (N) X Distance (m) = Work (N-m) Newton-Meter (Joule)– Unit measure for work.

6. Notes: Example: Lift a bag that weighs (Force) 25 Newtons a distance of 2 meters. Example: Lift a bag that weighs (Force) 25 Newtons a distance of 2 meters. F (Newtons) x d (meters)= W (Newton-meters) 25 N x 2m = 50 N-m (Joules)

7. Video (take notes) U:\Lesson-video\Physics\p-8-Work Defined 2 minutes.asfU:\Lesson-video\Physics\p-8-Work Defined 2 minutes.asfU:\Lesson-video\Physics\p-8-Work Defined 2 minutes.asfU:\Lesson-video\Physics\p-8-Work Defined 2 minutes.asf

8. Investigate how a motor’s power is calculated Investigate how a motor’s power is calculated

9. Read Text – Pg. 84 Read Text – Pg. 84 Watch Video (notes) VideoVideo 1 (2 minutes) Video

10. Power Defined: Power Defined:  Power is the rate at which work is done.  Power = work divided by the time it took to do the work

11. Power Defined: Power = Work Power = Work Time Time The Watt is the common unit of measure for power.

12. Power Defined: 1 Watt is defined as 1 joule (J) of work per second. 1 Watt is defined as 1 joule (J) of work per second.

13. Power calculation: A Girl pushes a box at a steady pace with a force of 8.0 N. She moves the box 3.0 m in 5.0 sec. What is her power output? A Girl pushes a box at a steady pace with a force of 8.0 N. She moves the box 3.0 m in 5.0 sec. What is her power output?

14. Power calculation: First, calculate work: 8.0 N x 3m = 24 Nm (joules) Next, calculate power: 24 joules / 5 = 4.8 watts

15. Power calculation: A motor steadily lifts a load that weighs 5.0 N a distance of 1.5 m in A motor steadily lifts a load that weighs 5.0 N a distance of 1.5 m in 2.0 s. What is the power output of the motor? 2.0 s. What is the power output of the motor?

16. Power calculation: Work: 5 N x 1.5 m = 7.5 Nm (joules) Power: 7.5 joules / 2 = 3.75 watts

17. 5. Materials:  Electric Motor  Motor Pulley with nail  Motor clamp  Knife switch  Stopwatch

18. 5. Materials:  Pegboard assembly  4 Batteries & holders  Wires with clips  Paper Clip  Meter stick  11 washers  Newton Scale

19. Methodology:Reflection: Movie (Notes) Video power advanced (27 minutes) or 7-11 27 Video circuits 24 minutes Video circuits 24 minutes