Chapter 21 Transportation Power

1. Chapter 21Transportation Power Introduction to Technology by Pierce and Karwatka Go to Unit 7 Presentation REVIEW

2. Chapter 21Transportation Power External Combustion Engines Internal Combustion Engines Electric Motors Section A Section B Section C EXIT MENU REVIEW

3. Section 21A External Combustion Engines EXIT MENU REVIEW

4. Wind Water Animals Since then many new kinds of engines have developed, starting with the steam engine in 1712. Section 21A External Combustion Engines What are some types of transportationpower of the past? EXIT MENU REVIEW

5. Steam engines are an example of an external combustion engine. Section 21A External Combustion Engines How do steam engines work? • A piston is driven by steam in a back and forth motion. • This motion turns a circular flywheel that is connected to the vehicle’s wheels. EXIT MENU REVIEW

6. Section 21A External Combustion Engines What are steam turbines? • A turbine is powered by steam and is a continually spinning disk that resembles a pinwheel. EXIT MENU REVIEW

7. Section 21B Internal Combustion Engines EXIT MENU REVIEW

8. The burning in an internal combustion engine is internal (inner), like in your family car. Section 21B Internal Combustion Engines Where does burning take place in an internal combustion engine? EXIT MENU REVIEW

9. Section 21B Internal Combustion Engines Two types of internal combustion engines; four stroke and two stroke • Four-stroke and two-stroke engines create power much like you may use upward and downward strokes to pedal your bicycle. EXIT MENU REVIEW

10. Section 21B Internal Combustion Engines How do gasoline engines produce power for automobiles? • Gasoline engines operate with a four-stroke cycle. • Reciprocating (up-and-down) motion is changed to rotary motion by a crankshaft. EXIT MENU REVIEW

11. Diesel engines are usually used for larger vehicles and require a special fuel system. Section 21B Internal Combustion Engines How are diesel engines different from gasoline engines? • Theignitionsystem of a diesel uses hot air rather than a spark plug used in gasoline engines. EXIT MENU REVIEW

12. Gas turbines are more reliable and require less maintenance. Gas turbines are smaller and lighter than other engines with similar power ratings. Section 21B Internal Combustion Engines Why do commercial airplanes use gas turbines instead of gasoline engines? EXIT MENU REVIEW

13. Oxygen does not exist in space. Only rocket engines can travel in space because they carry oxygen with them. Section 21B Internal Combustion Engines Why are rocket engines used for sending satellites into orbit? EXIT MENU REVIEW

14. Section 21C Electric Motors EXIT MENU REVIEW

15. Subways Electric trains Elevators Escalators Rides in amusement parks Section 21C Electric Motors Can you name some transportation vehicles that use electric motors? EXIT MENU REVIEW

16. The electricity is sent by wires to electrical motors directly connected to the driving wheels. Section 21C Electric Motors How do electric trains work? EXIT MENU REVIEW

17. E85 Electric Fuel Cell Hydrogen Hybrid Section 21C Electric Motors Alternative Energy Transportation EXIT MENU REVIEW

18. Review Questions • What kind of engine was the first to be invented? Check Answer • What is used in cars to turn reciprocating motion into rotary motion? Check Answer Check Answer • What is a hybrid car? EXIT MENU

19. Illustration Credits Digital Vision Ian Warpole Index Stock, HIRB