Table of contents

0. Math Review31m
- Math Review
  31m
1. Intro to Physics Units1h 29m
2. 1D Motion / Kinematics3h 56m
3. Vectors2h 43m
4. 2D Kinematics1h 42m
5. Projectile Motion3h 6m
6. Intro to Forces (Dynamics)3h 22m
7. Friction, Inclines, Systems2h 44m
8. Centripetal Forces & Gravitation7h 26m
9. Work & Energy1h 59m
10. Conservation of Energy2h 54m
11. Momentum & Impulse3h 40m
12. Rotational Kinematics2h 59m
13. Rotational Inertia & Energy7h 4m
14. Torque & Rotational Dynamics2h 5m
15. Rotational Equilibrium3h 39m
16. Angular Momentum3h 6m
17. Periodic Motion2h 9m
18. Waves & Sound3h 40m
19. Fluid Mechanics4h 27m
20. Heat and Temperature3h 7m
21. Kinetic Theory of Ideal Gases1h 50m
22. The First Law of Thermodynamics1h 26m
23. The Second Law of Thermodynamics3h 11m
24. Electric Force & Field; Gauss' Law3h 42m
25. Electric Potential1h 51m
26. Capacitors & Dielectrics2h 2m
27. Resistors & DC Circuits3h 8m
28. Magnetic Fields and Forces2h 23m
29. Sources of Magnetic Field2h 30m
30. Induction and Inductance3h 38m
31. Alternating Current2h 37m
32. Electromagnetic Waves2h 14m
33. Geometric Optics2h 57m
34. Wave Optics1h 15m
35. Special Relativity2h 10m

9. Work & Energy

Intro to Energy & Kinetic Energy

Physics

9. Work & Energy

Intro to Energy & Kinetic Energy

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Multiple Choice

How are kinetic energy and potential energy related in a closed system?

Potential energy is converted into kinetic energy, but the total energy decreases over time.

The total energy is conserved, meaning the sum of kinetic and potential energy remains constant.

Kinetic energy is always greater than potential energy in a closed system.

Kinetic energy and potential energy are unrelated and vary independently.

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Verified step by step guidance

Begin by understanding the concept of a closed system in physics. A closed system is one where no energy is lost to the surroundings; energy can be transformed within the system but the total energy remains constant.

Recognize the principle of conservation of energy. In a closed system, the total energy, which is the sum of kinetic energy (KE) and potential energy (PE), remains constant over time. This is expressed as:

E = KE + PE

Understand the transformation between kinetic and potential energy. In many physical systems, potential energy can be converted into kinetic energy and vice versa. For example, in a pendulum, potential energy is highest at the peak of its swing and is converted to kinetic energy as it moves downward.

Consider examples of energy conservation. In a roller coaster, at the highest point, the potential energy is maximum and kinetic energy is minimum. As it descends, potential energy decreases while kinetic energy increases, but the total energy remains constant.

Clarify misconceptions: Kinetic energy is not always greater than potential energy in a closed system, nor are they unrelated. They are interdependent and their sum is conserved, meaning they can transform into each other while maintaining the total energy constant.