1 / 18

Light (simply)

Light (simply). A Simple Review for Complex Seniors. EM Radiation. Light is caused by high energy electrons that move from higher energy shells to lower energy shells. The bundle of energy that they give off is called a “photon”. Photons travel through a vacuum at 3x10 8 m/s. model.

carla-bradley
Download Presentation

Light (simply)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Light (simply) A Simple Review for Complex Seniors

  2. EM Radiation • Light is caused by high energy electrons that move from higher energy shells to lower energy shells. The bundle of energy that they give off is called a “photon”. • Photons travel through a vacuum at 3x108 m/s model

  3. Sources of Light • Luminous sources are objects that emit light waves . The sun is a luminous body. • Illuminated objects reflect or transmit light that is incident upon them. The Moon is an illuminated body. • Transparent - transmits light • Translucent - transmit, but reflects some light. • Opaque - reflects all light

  4. Quantity of Light • The rate at which energy is emitted from a luminous body is called the luminous flux. (P) • Measured in lumen. (lm) • A 100W light bulb emits 1750 lumen.

  5. Inverse-Square Relationship

  6. Luminous Intensity • The flux that falls on 1m2 of the inside of a 1 meter radius sphere. • Intensity is flux/4π and is measured in candela, (cd).

  7. Ray Model of Light • These photons travel in straight line paths. • Used to demonstrate the ways that light interacts with other objects.

  8. Wave-Particle Duality • Christiaan Huygens- Dutch (1629-1695) • presents a “wave model of light” to explain diffraction patterns. • Newton- English (1643-1727) • presents a “corpuscle (particle) model of light” in competition.

  9. Light as a Wave • Thomas Young’s Double Slit Experiment

  10. James Maxwell: studied other electromagnetic waves: • Suggested light was an EM wave • Results confirmed.

  11. Light as a Particle

  12. Albert Einstein • Wins Nobel prize for explaining that light is a particle AND a wave at the same time. • States that light is carried in packets of different energies. • Called quanta. • Blue has more energy than red no matter the intensity. • Why electrons are ejected for blue but not red.

  13. RGBY?!?!?!? WHY!?!?!They are counting on you to be stupid!

  14. Color • Color works by absorption or reflection of specific wavelengths of light. • Green objects reflect green light and absorb all others. Magenta objects absorb all green and reflect blue and red.

  15. How about the weird stuff? • Shine red light on a green object. What do you see? • A.) red. • B.) green • C.) orangey greenish • D.) black

  16. Why? GUMMY BEARS AND LASERS!

More Related