1 / 15

Energy & Its Impact on Global Society

Energy & Its Impact on Global Society. Jerome K. Williams, Ph.D. Saint Leo University Dept. Mathematics & Sciences. Chapter 2: Energy Mechanics. Critical Thinking in Science Forms of Energy Primary Energy Souces & Energy Conversions Motion. Critical Thinking in Science.

alina
Download Presentation

Energy & Its Impact on Global Society

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Energy & Its Impact on Global Society Jerome K. Williams, Ph.D. Saint Leo University Dept. Mathematics & Sciences

  2. Chapter 2: Energy Mechanics • Critical Thinking in Science • Forms of Energy • Primary Energy Souces & Energy Conversions • Motion

  3. Critical Thinking in Science • Scientists seek to understand the physical world and how it works • Making Observations • Formulating Hypothesis • Testing Hypothesis by Experimentation

  4. Critical Thinking in Science • A tentative statement that tries to generalize a series of observations is a hypothesis. • A hypothesis that has been supported by a large number of observations and experiments is called a theory.

  5. Forms of Energy • Mechanical Energy • Two Kinds • Kinetic Energy (KE) – energy of motion • Potential Energy (PE) –energy of position

  6. Forms of Energy

  7. Forms of Energy • Chemical Energy – use fossil fuels & food for energy • Nuclear Energy- energy found in atomic nucleus • Thermal Energy: transfer heat between objects • Electrical Energy – energy produced at power plants or stored in batteries • Light (Radiant) Energy – also called electromagnetic radiation (ER); this covers a wide range of sources from radio and TV waves to X-rays and solar energy

  8. Primary Energy Sources & Energy Conversions • Primary Energy Sources • Chemical • Nuclear • Radiant • Energy Conversion Processes are how primary energy sources are converted to an end use (powering a car, heating a home, using a laptop computer, etc.)

  9. Primary Energy Sources & Energy Conversions

  10. Motion • Speed = distance traveled per unit time • Velocity = similar to speed except it must include direction of travel • Acceleration = change in velocity per unit time

  11. Motion

  12. Motion • Force = push or pull on an object by other objects in environment • Newton’s 2nd Law of Motion = acceleration of an object is directly proportional to the net force acting on it and inversely proportional to the object’s mass

  13. Motion • Units for Speed: • Examples m/s, km/h, ft/s, mph • Units for Force: • Examples Newton (N), Pound (lb) • Conversion Factors: 1 lb = 4.45 N • Table 2.4

  14. Example Problem 2.1 • A 2000 kg car is acted on by a force of 6000 N by its wheels. Also acting on the car is a force of friction of 800 N. What is the car’s acceleration? • Answer: 2.6 m/s2

  15. Example Problem 2.2 • Brakes are applied to a 1900 kg car moving at 80 km/h. In a time of 4.0 seconds, its velocity decreases uniformly to 30 km/h. What is the net force acting on the car? • Answer: 6650 N

More Related