Special Theory of Relativity

• Newtonian mechanics


  Based on the application of Newton's three laws of motion which assume that the concepts of distance, time, and mass are absolute
• Special Relativity


  Theory that explains how space and time are linked for objects that are moving at constant speed in a straight line
• The speed of light is 186,000 miles per second
• Albert Einstein

  Physicist who developed the special theory of relativity
• Postulates of Special Relativity

  There are 2 postulates
• Use of special relativity in everyday life

  • Global Positioning System (GPS)
• Principles of special relativity

  Principle of relativity and the principle of the speed of light
• The speed of light is independent of the motion of the source and the observer
• Postulate of special relativity

  The laws of physics are the same for all observers in uniformly moving frames of reference
• Physical properties dependent on observer speed in special relativity

  • Energy
  • Length
  • Time
• According to special relativity, physical laws are the same in frames of reference which move at uniform velocity
• Electromagnetic spectrum

  The range of wavelengths or frequencies over which electromagnetic radiation extends
• James Clerk Maxwell


  Physicist who demonstrated that electric and magnetic fields travel through space as waves moving at the speed of light
• Visible light


  A form of electromagnetic radiation that is observable to most human eyes
• According to Newton's first law of motion, a moving object that is not acted on by an unbalanced force will remain in motion
• Visible light


  A form of electromagnetic (EM) radiation that is observable to most human eyes
• Newton's first law of motion

  • A moving object that is not acted on by an unbalanced force will remain in motion
• In order to understand Physics, one must start with a thoughtful learning experience of motion, time, and space
• Since motion, time, and space are in every activity of our daily living, one can fully understand our interaction with everything here on Earth and even everything outside it
• There is a conflict between Newtonian Mechanics and the Theory of Electromagnetism
• The Special Theory of Relativity resolved the conflict between Newtonian Mechanics and the Theory of Electromagnetism
• Electromagnetic Spectrum of light

  Complete the table
• Newton's Second Law of Motion (F=ma)

  1. Find the net force required to give an automobile of mass 1600 kg an acceleration of 4.5 m/s2

  2. Give the mass of an object that is experiencing a net force of 200 N and an acceleration of 500 m/s2

  3. Find the acceleration of a car weighing 100 kg and has a force of 100 N

  4. What is the acceleration of a wagon with a mass of 20 kg if a horizontal force of 64 N is applied to it

  5. An object accelerates 12.0 m/s2 when a force of 6.0 newtons is applied to it. What is the mass of the object
• Marissa sent a birthday greeting card to Anna through Facebook
• Marissa sent the greeting at 12:00 am of July 30


  Anna's birthday is on July 30
• Anna thought it was an advanced greeting since it's just July 29 in Niue
• There is a 19 hour difference between Anna's place and Marissa's place
• The Special Theory of Relativity was developed by Albert Einstein in 1905
• The Special Theory of Relativity resolved the conflict between James Clerk Maxwell's Theory of Electromagnetism and Isaac Newton's Three Laws of Motion
• Newtonian Mechanics


  • Space (distance), time, and mass are absolute
  • Objects move in a straight line
  • No changes in space or time regardless of location or speed
• Maxwell's Electromagnetic Theory of Light

  • Light is an electromagnetic wave that moves at a constant speed of 186,000 miles per second
• According to Newtonian physics, all speeds are relative
• According to Maxwell's theory, light in a vacuum moves at 186,000 miles per second and does not change for all observers and situations
• Consistent law principle

  All motions are relative to the selected reference frame or viewpoint
• Constancy of speed


  Light moves at a speed of 186,000 miles per second and is the same for all observers' viewpoint
• The two postulates of the Special Theory of Relativity clarify that if two events happen at different places, it is not always likely to say which of the two events happens first or that they occur at the same time
• Newtonian mechanics

  Grounded on the use of Newton's laws
• Space, time, and mass

  Absolute in Newtonian mechanics
• Newton's second law

  Objects in the environment move in a straight line
• Light moves at a speed of 186,000 miles per second