Science

• Light


  Essential in our life, allows us to see things
• Light


  • Can be from natural sources like the sun, or artificial sources like candles and light bulbs
  • Enables brightness, darkness, contrast, and colors
• Light interacts with objects in its path
• Warm-Up: See the Light

  1. Cover the inside of a shoebox with black art paper

  2. Place a material inside the box

  3. Turn on the flashlight and let the light strike the material

  4. Observe how the light interacts with the material
• Reflection


  The bouncing of light, when reflected light reaches the eyes, the lens creates an image on the retina, the optic nerve sends a message to the brain which interprets the image
• Reflection


  • Light reflects and produces an image on smooth, polished surfaces like mirrors
  • Light may also be reflected from still, undisturbed clear water
  • Reflected image can be laterally inverted or inverted from left to right
• Refraction


  The bending of light when it travels from one medium to another with a different speed
• Refraction


  • Light traveling from air to water, the light changes direction and becomes slower as it travels through the water
  • Refraction can result in images that may be different in size and shape than the actual object
• Lens


  A transparent material that refracts light and produces an image, can be convex or concave
• Lens


  • Magnifying glass uses lenses to magnify objects
• Absorption


  Light is converted into heat when absorbed by a material, instead of being reflected
• White objects reflect all the colors of light, while black objects absorb all light that hits them</b>
• Materials based on how they transmit light

  • Transparent (transmit all light)
  • Translucent (transmit some light)
  • Opaque (do not transmit light)
• Transparent materials


  • Glass windows, clear plastic
• Absorption


  Light is converted into heat
• White objects reflect all the colors of light, while black objects absorb all light that hits them
• Black objects heat up faster than any other colored object
• Transparent materials


  • Can transmit all the light, you can see through them
• Transparent objects


  • Glass windows
  • Water
• Translucent materials


  • Can transmit only some light, you can see through them but not as clearly
• Translucent objects


  • Tea drink
  • Stained glass
  • Sunglasses
• Opaque materials


  • Do not transmit light, they block the passage of light
• Opaque object


  • Rock
• When light hits an opaque object, some parts are reflected and some are absorbed, heating the object
• Realizing how different objects transmit light allows one to know which type of material will be used for a certain purpose
• Types of windows


  • Transparent windows
  • Translucent windows
  • Wood window cover
• Shadow


  Formed when light is blocked, in areas where light is not transmitted
• Opaque objects have darker shadows than translucent objects because not all light is blocked by translucent objects
• Ways light can interact with objects

  • Reflection
  • Refraction
  • Absorption
  • Transmission
• Reflection


  The bouncing of light as it strikes a surface
• Refraction


  The bending of light as it passes through materials
• Absorption


  Absorbing light and converting it to heat
• How materials can be classified by how they transmit light

  • Transparent
  • Translucent
  • Opaque
• Motion is a change in the position of an object over time
• Frame of reference


  A fixed point of position used to observe the motion of an object
• To completely define the motion of an object, one should note the change in its position over time in relation to the frame of reference
• Motionless/at rest/stationary


  An object that does not change its position with respect to the frame of reference
• Motion


  An object that changes its position from one point to another with respect to the frame of reference
• Distance


  How far two objects (or points) are from one another, the total space covered by a moving object
• Displacement


  Distance with direction, the shortest distance covered by an object from the initial to its final position