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Chapter 1: Introduction

  • The equation equals MC squared is famous but few people know its meaning or origin

  • Deriving the equation and understanding its meaning

  • Insight into Einstein's theory of special relativity

Chapter 2: Mechanics and Frames of Reference

  • Mechanics describes how bodies change position in space over time

  • Observing the motion of a stone dropped from a moving train

  • Stone appears to descend in a straight line from the train's frame of reference

  • Stone appears to fall in a parabolic curve from the platform's frame of reference

  • Using a system of coordinates to describe motion relative to a frame of reference

Chapter 3: Principle of Inertia and Inertial Frames of Reference

  • The fundamental law of mechanics: A body continues in rest or uniform motion in a straight line unless acted upon by an external force

  • Principle of inertia

  • An inertial frame of reference is a non-accelerating frame of reference

  • Einstein's theory of special relativity focuses on inertial frames of reference

Chapter 4: Principle of Relativity

  • Introduced by Galileo in his dialogue concerning the 2 chief world systems

Chapter 2: Particular Moving Clock

  • Einstein's experiment with the speed of light

    • Spaceship traveling at 200,000 km/s relative to the road

    • Beam of light travels past at 300,000 km/s relative to the road

    • Speed of light relative to the spaceship is 100,000 km/s

    • Experiment shows light traveling 300,000 km/s relative to spaceship and road

    • Conclusion: Sense of space and time is not the same for a person standing still and a person moving

  • Measuring the duration of time

    • Simple clock with parallel mirrors separated by one meter

    • Light signal reflects off mirrors, making a tick every time it moves up and a tock every time it comes down

    • Two clocks with same length are synchronized

    • Light always travels at the same speed

  • Comparison of stationary and moving clocks

    • Stationary clock takes time T Naught for one tick-tock

    • Moving clock on a train takes longer path due to train's motion

    • Observer sees light taking a zigzag path in the moving clock

    • Path taken by light in moving clock is longer than in stationary clock

Chapter 1: Introduction

  • The train is moving with velocity V relative to the platform

  • The time taken for light to travel from bottom mirror to top mirror is big t

Chapter 2: Pythagoras' Theorem

  • Using Pythagoras' theorem to find a relationship between the sides of a right angle triangle

  • CT squared = 1 squared + vt squared

  • Rearranging for t, the time taken for a tick of the moving clock: t = 2 / square root of (c squared - v squared)

Chapter 3: Time Dilation

  • Expressing t in terms of t naught, the time taken for the tick tock of the stationary clock: t = t naught / square root of (1 - v squared / c squared)

  • Gamma (γ) is the factor that tells us the difference between t and t naught

  • If v = 0, then gamma = 1 and t = t naught

  • If v > 0, then gamma > 1 and t > t naught

  • All moving clocks run slower by the same amount to preserve the principle of relativity

  • Time dilation is the difference in elapsed time between stationary and moving frames of reference

Chapter 4: Time Dilation at the Speed of Light

  • As v approaches c, gamma approaches infinity and t tends to infinity

  • The tick tock of the moving clock would get slower and eventually freeze

Chapter 5: Conclusion

  • Time dilation is a prediction of Einstein's theory of special relativity

  • Time itself appears to be slower in the moving train

Chapter 3: Energy Of Object

  • Usane Bolt example

    • Calculating time dilation factor

    • t is essentially the same as t naught

  • Time dilation with muons

    • Muons created in upper atmosphere decay after 2.2 microseconds

Chapter 1: Introduction

  • The equation equals MC squared is famous but few people know its meaning or origin

  • Deriving the equation and understanding its meaning

  • Insight into Einstein's theory of special relativity

Chapter 2: Mechanics and Frames of Reference

  • Mechanics describes how bodies change position in space over time

  • Observing the motion of a stone dropped from a moving train

  • Stone appears to descend in a straight line from the train's frame of reference

  • Stone appears to fall in a parabolic curve from the platform's frame of reference

  • Using a system of coordinates to describe motion relative to a frame of reference

Chapter 3: Principle of Inertia and Inertial Frames of Reference

  • The fundamental law of mechanics: A body continues in rest or uniform motion in a straight line unless acted upon by an external force

  • Principle of inertia

  • An inertial frame of reference is a non-accelerating frame of reference

  • Einstein's theory of special relativity focuses on inertial frames of reference

Chapter 4: Principle of Relativity

  • Introduced by Galileo in his dialogue concerning the 2 chief world systems

Chapter 2: Particular Moving Clock

  • Einstein's experiment with the speed of light

    • Spaceship traveling at 200,000 km/s relative to the road

    • Beam of light travels past at 300,000 km/s relative to the road

    • Speed of light relative to the spaceship is 100,000 km/s

    • Experiment shows light traveling 300,000 km/s relative to spaceship and road

    • Conclusion: Sense of space and time is not the same for a person standing still and a person moving

  • Measuring the duration of time

    • Simple clock with parallel mirrors separated by one meter

    • Light signal reflects off mirrors, making a tick every time it moves up and a tock every time it comes down

    • Two clocks with same length are synchronized

    • Light always travels at the same speed

  • Comparison of stationary and moving clocks

    • Stationary clock takes time T Naught for one tick-tock

    • Moving clock on a train takes longer path due to train's motion

    • Observer sees light taking a zigzag path in the moving clock

    • Path taken by light in moving clock is longer than in stationary clock

Chapter 1: Introduction

  • The train is moving with velocity V relative to the platform

  • The time taken for light to travel from bottom mirror to top mirror is big t

Chapter 2: Pythagoras' Theorem

  • Using Pythagoras' theorem to find a relationship between the sides of a right angle triangle

  • CT squared = 1 squared + vt squared

  • Rearranging for t, the time taken for a tick of the moving clock: t = 2 / square root of (c squared - v squared)

Chapter 3: Time Dilation

  • Expressing t in terms of t naught, the time taken for the tick tock of the stationary clock: t = t naught / square root of (1 - v squared / c squared)

  • Gamma (γ) is the factor that tells us the difference between t and t naught

  • If v = 0, then gamma = 1 and t = t naught

  • If v > 0, then gamma > 1 and t > t naught

  • All moving clocks run slower by the same amount to preserve the principle of relativity

  • Time dilation is the difference in elapsed time between stationary and moving frames of reference

Chapter 4: Time Dilation at the Speed of Light

  • As v approaches c, gamma approaches infinity and t tends to infinity

  • The tick tock of the moving clock would get slower and eventually freeze

Chapter 5: Conclusion

  • Time dilation is a prediction of Einstein's theory of special relativity

  • Time itself appears to be slower in the moving train

Chapter 3: Energy Of Object

  • Usane Bolt example

    • Calculating time dilation factor

    • t is essentially the same as t naught

  • Time dilation with muons

    • Muons created in upper atmosphere decay after 2.2 microseconds