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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

What is the source of almost all energy on Earth?

Geothermal energy

The Sun

Wind energy

Nuclear reactions

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Verified step by step guidance

Understand that energy on Earth comes from various sources, including the Sun, geothermal energy, wind energy, and nuclear reactions.

Recognize that the Sun is the primary source of energy for Earth. It provides energy through solar radiation, which drives weather patterns, ocean currents, and supports photosynthesis in plants.

Consider how geothermal energy is derived from the heat stored within the Earth, which is a result of radioactive decay and residual heat from the planet's formation.

Acknowledge that wind energy is generated by the movement of air, which is driven by temperature differences caused by solar heating of the Earth's surface.

Note that nuclear reactions, such as those occurring in nuclear power plants, provide energy through the process of nuclear fission, but this is not a natural source of energy like the Sun.