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Searching for ## Relativity

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Explore the full path to learning Relativity

Physics

You will get to Take a close look at Einstein’s theory of special relativity, and what it predicts about the ability to accelerate an object infinitely.

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After completing this tutorial, you will be able to complete the following:

- State that the speed of light is the upper speed limit in the universe.
- Explain how to calculate the kinetic energy of particles that are moving closer to the speed of light.

How is kinetic energy calculated?

~ To find kinetic energy, the amount of energy in an object's static state is subtracted from the total energy found using Einstein's formula, E0 = mc˛.

What happens to the denominator in the kinetic energy formula as an object's speed increases?

~ The denominator gets smaller as the speed of an object increases, or moves closer to the speed of light.

How does an increase in speed affect the energy required to accelerate an object?

~ As the speed of an object increases, the energy required to accelerate it also increases.

Why can't an object that has mass move at the speed of light?

~ An object that has mass cannot move at the speed of light because as the speed of an object increases, the energy required to accelerate it also increases. At the speed of light, the denominator of the equation becomes zero, which suggests that infinite energy is necessary to accelerate something with mass to this speed. This amount of energy does not exist in the universe. Therefore, the speed of light is an upper limit that objects with mass cannot reach.

Approximate Time | 2 Minutes |

Pre-requisite Concepts | Students should be able to define the following terms: conductor, electrical outlet, and electric plug. |

Course | Physics |

Type of Tutorial | Animation |

Key Vocabulary | Einstein, mass-energy relationship, total energy |