My notes

• Light


  • Travels in straight lines from the light source
  • Travels through space as waves of energy
  • Travels very fast at a speed of approximately 300 000 km/s
  • Movement of light will differ in the kind of material that it hits
  • Can pass through different objects at different speeds
  • Can bounce off from objects
• Sources of light


  • Natural light
  • Artificial light
• Natural light


  Light that comes from natural sources such as the sun, stars, lightning, and fireflies
• Natural light sources


  • Sun
  • Stars
  • Lightning
  • Fireflies
• Luminous objects


  Objects that release light energy
• Artificial light


  Light that comes from artificial sources such as light bulbs/lamps and flashlights
• Nonluminous objects


  Objects that do not give off light but we can still see them because they reflect the light from an actual source of light
• Artificial light sources


  • Light bulbs
  • Lamps
  • Flashlights
• Translucent Object


  An object that allows some light to pass through, but not enough to see a clear image on the other side.
• The color of an object depends on how much red, blue, green, yellow, orange, and violet light bounces off its surface and enters our eye.
• Black is the absence of any color.
• Heat- is the transfer of thermal energy . It can be transferred to a another material, area, or body that has a cooler temperatures
• Temperature - is the measurement of how hot or how cold an material /system is
• There are three way on how heat can be transferred , conduction, covection, and Radiation
• Radiation - The transfer of heat between objects without touching them. All objects emit electromagnetic radiation (heat) at all times. Some of this radiation is absorbed by nearby objects while the rest escapes into space.
• Convection - The movement of heated air or liquid away from the source of heat. Convection currents occur because warm liquids and gases expand and become less dense than their surroundings.
• Conduction - The process by which heat moves from one molecule to another without moving itself. This occurs when two objects with different temperature come into contact with each other.