9. Work & Energy

Intro to Energy & Kinetic Energy

Where does the kinetic energy formula come from?

Both blocks will have the same final kinetic energy and the same final speed.

Block A will have a greater final kinetic energy and a greater final speed.

Block B will have a greater final kinetic energy and a greater final speed.

The blocks will have the same final kinetic energy, but block B will be moving faster.

The blocks will have the same final velocity, but block B will have greater kinetic energy.

The blocks will have the same final kinetic energy, but block A will be moving faster.

Block A has mass <math display="inline"><mrow><mn>20</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">kg</mi></mrow></math> and block B has mass <math display="inline"><mrow><mn>50</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">kg</mi></mrow></math>. Starting from rest, the two blocks are pushed by identical forces through a distance of <math display="inline"><mrow><mn>10</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">m</mi></mrow></math>. Which block (if either) is going faster at end of the <math display="inline"><mrow><mn>10</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">m</mi></mrow></math>? Which block (if either) has the greatest kinetic energy at the end of the <math display="inline"><mrow><mn>10</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">m</mi></mrow></math>?

Work and Energy

What is the kinetic energy of a <math display="inline"><mrow><mn>500</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">kg</mi></mrow></math> car traveling at <math display="inline"><mrow><mn>27</mn><mo rspace="thickmathspace">&#x2062;</mo><mrow><mi mathvariant="normal" class="MathML-Unit">m</mi><mo>/</mo><mi mathvariant="normal" class="MathML-Unit">s</mi></mrow></mrow></math> (about <math display="inline"><mrow><mn>60</mn><mo rspace="thickmathspace">&#x2062;</mo><mi mathvariant="normal" class="MathML-Unit">mph</mi></mrow></math>)?

About 50,000 years ago, a meteor crashed into the earth near present-day Flagstaff, Arizona. Some estimates suggest this meteor had a mass of about 1.4×108 kg and released 1×1016 J of energy when it slammed into the Earth. Calculate the approximate speed of this meteor before impact.

Kinetic Energy: Example Problems

At what speed does a 1000 kg compact car have the same kinetic energy as a 20,000 kg truck going 25 km/h?

A particle with mass m and velocity v has kinetic energy K. What is the kinetic energy of a particle with mass m/2 and velocity 2v?

A mother has four times the mass of her young son. Both are running with the same kinetic energy. What is the ratio v(son)/v(mother) of their speeds?

Intro to Energy & Types of Energy

(c) Is it reasonable that a 30-kg child could run fast enough to have 100 J of kinetic energy?

Energy | Physics with Professor Matt Anderson | M11-01

Learn the toughest concepts covered in Physics with step-by-step video tutorials and practice problems by world-class tutors

Patrick

Physics

https://static.studychannel.pearsonprd.tech/courses/physics/thumbnails/physics

#FFFFFF

Zak's Lab

Professor Dave Explains

Step by Step Science

Patrick Ford

Physics with Professor Matt Anderson

1. Intro to Physics Units

2. 1D Motion / Kinematics

3. Vectors

4. 2D Kinematics

5. Projectile Motion

6. Intro to Forces (Dynamics)

7. Friction, Inclines, Systems

8. Centripetal Forces & Gravitation

10. Conservation of Energy

11. Momentum & Impulse

12. Rotational Kinematics

13. Rotational Inertia & Energy

14. Torque & Rotational Dynamics

15. Rotational Equilibrium

16. Angular Momentum

17. Periodic Motion

18. Waves & Sound

19. Fluid Mechanics

20. Heat and Temperature

21. Kinetic Theory of Ideal Gases

22. The First Law of Thermodynamics

23. The Second Law of Thermodynamics

24. Electric Force & Field; Gauss' Law

25. Electric Potential

26. Capacitors & Dielectrics

27. Resistors & DC Circuits

28. Magnetic Fields and Forces

29. Sources of Magnetic Field

30. Induction and Inductance

31. Alternating Current

32. Electromagnetic Waves

33. Geometric Optics

34. Wave Optics

36. Special Relativity

[BOOK PHYS] !CLUTCH

Intro to Calculating Work

Power

Net Work & Work-Energy Theorem

Work On Inclined Planes

Work As Area Under F-x Graphs

Work By Springs

General Chemistry

Jules

Study the key concepts of Physics with descriptive videos, questions, and more

General Biology

Jason

Financial Accounting

Brian

Dive deep into Psychology with videos, practice problems, and more.

Psychology

Microeconomics

The first in a two-course sequence introduces the basic structure and functions of the human body

Anatomy & Physiology

College Algebra covers algebraic topics and skills necessary to succeed in college-level math

College Algebra

Organic Chemistry

Johnny

Genetics

Kylia

GOB Chemistry

Microbiology

Cell Biology

Analytical Chemistry

Study topics incliding trogonometric functions, identities and equations, solutions of triangles, complex numbers, and other topics as time permits

Trigonometry

Learn the toughest concepts covered in Precalculus with step-by-step video tutorials and practice problems by world-class tutors

Precalculus

Biochemistry

Macroeconomics

Chemistry

Biology

Math

Business

Social Sciences

Michelle Barry Franco

Building Great Presentations

Eric Zackrison, PhD

Critical Thinking And Problem Solving

Sam Bennett

Embracing Times Of Uncertainty

Nicole Tetreault, PhD

Emotional Intelligence Basics

Eugene Choi, PharmD

Enhancing Your Critical Thinking Skills

Jason Richardson, PsyD

Habits To Win Every Day

Alyssa Lowery, PhD

Having Powerful Advanced Conversations

Don Gilman, EdD

How To Influence & Persuade

Amy Matthews

Leadership Skills For Rising Stars

Listening To Lead

Michael Shermer, PhD

Making Decisions Under Uncertainty

Lynne Hurdle

Mistakes To Avoid When Resolving Conflict

Michael Veltri

Overcoming Decision Making Traps

Mike Vardy

Prioritizing Effectively

Secrets Of Effective Prioritization

Strategies To Build Up Your Creativity

Tools For Decision Making

Tutti Taygerly

Unleash And Advance Your Creativity

Winning Collaboration: How To Work More Effectively With Different Personalities

Writing Emails People Want To Read

Critical Thinking

Self Management

Digital Literacy

Collaboration

Communication

Analytical Thinking

Leadership

Flexibility/Adaptability

Innovation

Eric Zackrison

Nicole Tetreault

Dive deep into Python with videos and more.

Introduction to Python

Arianne Dee

Agile Project and Product Management

Agile & Product Management

Mariya Breyther 

Introduction to Microsoft Power BI

Microsoft Power BI

Chris Sorensen

Data Analysis Fundamentals with Excel

Data Analysis - Excel

Chris Sorensen & Ammul Shergill

Getting Started with  and Cryptocurrency

Introduction to Blockchain

George Levy

Learn Enough HTML, CSS and Layout to be Dangerous

HTML, CSS & Layout

Lee Donahoe & Michael Hartl

Learn Enough JavaScript to be Dangerous: A Tutorial Introduction to Programming with JavaScript