SCI. TECH.

• 'Linear Motion is a continuous change in position. It may be circular, repeating, or along a straight line. Linear Motion is motion on a straight line moving forward or backward'
• Distance vs Displacement

  Distance is the length that an object travelled; an absolute value meaning it can never be negative.
• Total distance and Total displacement


  Total distance and total displacement can be computed by adding the distances or displacements that the object traveled from a starting point
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  Speed tells you how fast an object is moving.
• Average speed


  This is the distance travelled by an object over a certain amount of time. Average speed = distance/time
• Acceleration

  Change in velocity over time
• Positive acceleration


  When an object is increasing in velocity over time
• Deceleration


  When an object is decreasing in velocity over time
• Zero acceleration


  When an object is moving at constant velocity
• Three ways to "Accelerate"

  • Speed Up
  • Slow Down
  • Change Direction
• Constant Acceleration


  Acceleration that does not change over time
• Formula for acceleration

  v final - v initial / t
• Displacement is the change in an object's position in a particular direction; may be a positive or negative value
• Velocity tells you how fast an object is moving in relation to a direction
• A wave is a disturbance that carries energy from place to place
• A wave does NOT carry matter with it! It just moves the matter as it goes through it.
• Some waves do not need matter to be able to move. These are called electromagnetic waves(or EM waves).
• Some waves MUST have a medium in order to move. These are called mechanical waves.
• Transverse waves: Waves in which the medium move sat right angles to the direction of the wave
• Crest: the highest point of the wave
• Trough: the lowest point of the wave
• Compression (or longitudinal) waves: Waves in which the medium moves back and forth in the same direction as the wave
• Compression: where the particles are close together
• Rarefaction: where the particles are spread apart
• Wavelength: The distance between one point ona wave and the exact same place on the nextwave.
• Frequency: How many waves go past a point in one second; unit of measurement is hertz (Hz).
• The higher the frequency, the more energy in thewave.
• Amplitude: How far the medium moves from rest position
• The closer together and further apart the particles are, the larger the amplitude.
• Wave speed: Depends on the medium in whichthe wave is traveling. It varies in solids, liquid sand gases.
• A mathematical way to calculate speed:wave speed = wavelength (in meters) x frequency (in Hz)= ?
• Reflection: When waves bounce off a surface.
• the law of reflection: If the surface is flat, the angle at which the wave hits the surface will be the same as the angle at which it leaves the surface (angle in = angle out).
• Refraction: Waves can bend.
• Diffraction: The bending of waves AROUND anobject.
• Small obstacle, large wavelength = large diffraction
• Light wave - form of EM wave that is propagated perpendicular to the source of energy, travel in a straight path
• Transmission - refers to the process where light passes through an object or medium without being absorbed.
• Absorption - occurs as light passes through a medium with the same natural frequency. As light travels through a medium, a portion of it is absorbed
• The ones who introduced the color of light: Isaac Newton and Rene Descartes