optics types of light 10l

properties of light

1. light energy travels very fast (c = 3.0 × 10^8 m/s)

2. light travels in a straight line but also as waves (electromagnetic waves)

3. radiates ( no medium needed)

electromagnetic spectrum

red has long waves but low energy

violet has high waves and high energy

radiation

form of electromagnetic energy ex. sunshine, x rays, radiant heating systems

light energy

form of electromagnetic radiation of a wavelength

photons - tiny packets of energy produced from the movement of atoms

incandescence

production of light as a result of high temp.

• incandescnes light bulbs

electric discharge

process of producing light by passing an electric current through a gas

• neon signs

• lightening

fluorescence

(phosphors — hg → UV → phosphors) immediate

immediate emission of visible light, a result of the absorption of UV light

• glow in the dark stickers

• fluorscence lights

phosphorescence

producing light by absorption of UV light, resulting in the emission of visible light over an extended period of time

glow in the dark stickers

chemi and bioluminscence (chemical reaction)

direct production of light as the result of a chemical reaction w little or no heat produced

chemi - glow sticks

bio - fireflies

triboluminscennce

production of light from friction, result of scratching crushing or rubbing certain crystals

leds

light produced as a result of an electric current flowing in semiconductors

laser

has one continuous straight line, same wavelength so same colour

laws of reflection

angle of incidence = angle of reflection

Oi and Or and normal lies in the same place

SALT

size - large small same

attitude - upright or inverted

location - object / image

type - virtual or real

virtual - light doesn’t meet and doesn’t interept usually the same orientation as an object can’t be projected, divergent

real - light converges and meets at a point

electromagnetic spectrum from highest to lowest

Gamma Rays

• • Used in cancer treatment (radiotherapy).

  • Emitted by radioactive substances and nuclear reactions.

  • Gamma-ray bursts in space.

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2. X-Rays

• • Medical imaging (e.g., X-rays of bones).

  • Airport security scanners.

  • Used in astronomy to observe stars and black holes.

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3. Ultraviolet (UV) Light

• • Causes sunburn (UV radiation from the Sun).

  • Sterilization of medical equipment.

  • Black lights and some insect traps.

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4. Visible Light

• • Rainbow colors (ROYGBIV: red, orange, yellow, green, blue, indigo, violet).

  • Sunlight, light bulbs, and lasers.

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5. Infrared (IR) Radiation

• • Heat emitted by objects (e.g., humans, stoves).

  • Used in remote controls and thermal imaging cameras.

  • Infrared astronomy to detect heat from celestial objects.

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6. Microwaves

• • Microwave ovens.

  • Satellite communications (e.g., GPS, weather forecasting).

  • Radar systems.

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7. Radio Waves

• • AM/FM radio broadcasting.

  • Television signals.

  • Cell phone and Wi-Fi communication.