Light can be a particle or wave and is responsible for sight. Several scientists studied light, including Newton, Huygens, Planck, and Maxwell. Newton believed light behaved as particles, while Huygens believed it behaved as waves. Planck later proposed light has both particle and wave properties. Maxwell combined concepts of light, electricity, and magnetism into his electromagnetic theory of light. Sources of light include the sun and artificial sources like bulbs. Brightness depends on distance from the light source and is measured in candela units. The electromagnetic spectrum arranges light by frequency, with red having the longest wavelength and lowest frequency.

1. ARCHIE A. DURAN

2. what is light???
responsible for the sense of sight.
light is a transverse and
electromagnetic wave.
travels in a straight path.

3. first to study light
Sir Isaac Newton
Christian Huygens
Max Planck
James Clerk Maxwell

4. Sir Isaac Newton
he believed that light
behaves like a particle.

5. Christian Huygens
he believed that light
behaves like a wave.

6. Max Planck
came up with what is
now known as the Dual-
Nature of Light.

7. Max Planck
He explained that light
can be a particle and
can also be a wave.

8. James Clerk Maxwell
he proposed the
electromagnetic theory
of light.

9. James Clerk Maxwell
He combined the concepts
of light, electricity and
magnetism to come up
with his theory forming
electromagnetic waves.

10. Sources of Light
Natural sources – like the sun
Artificial sources – like bulbs, lamps, candles
***luminous body – an object capable of producing its own
light.

11. energy to light
many forms of energy transformation can
produce light.
ex. in oil lamps (chemical -> light)
in fluorescent bulb (electricity -> light)

12. brightness
depends on the source and distance
from the source.
it also depends from person to person
(qualitative)
it can be computed (quantitative)

13. Candela (cd)
is the unit used to express the
brightness of an object
capable of producing light.

14. Electromagnetic
Spectrum
is the arrangement of electromagnetic
waves according to frequency

15. White Light
the visible part of the
electromagnetic spectrum that
can be seen by the human eye.
also known as visible light.

16. Wavelength

17. ROYGBIV
red has the longest wavelength
but lowest frequency.
violet has the shortest wavelength
but highest frequency

18. ROYGBIV
red has the lowest energy
violet has the highest energy

19. energy, frequency, wavelength
frequency = energy
frequency = energy
wavelength = frequency
wavelength = frequency

20. Health Issues
UV rays are highly energetic than other
spectral regions on its left. This could be
a possible reason why we are not advised to
stay under the sun after 9:00 in the morning.

21. Prolong use of mobile phones may
cause ear infection. This may be due
to a higher energy emitted by
microwaves used in cellular
phones than radio waves
commonly used in other
communication devices.

22. Prism
a material that splits light into
its different colors.
used by Sir Isaac Newton

23. Dispersion
is a phenomenon in which a
prism separates white light into
its component colors.

24. Color Spectrum

25. WHY???

29. MENTAL EXERCISE

30. 1. What part of the
human body can
perceive light?

31. 2. Sir Isaac Newton
believed that light
behaves like a
_______.

32. 3. __________
proposed the dual nature
of light.

33. 4. In oil lamps, light is
produced through the
conversion of _______
energy to light energy.

34. 5. An object that has the
ability to produce light.

35. 6. Unit used to express
luminous intensity.

36. 7. Light wave does not
need a medium to travel
and thus classified as
_____.

37. 8. An object that splits
light into its different
colors.

38. 9. The different colors of
light is known as
_p_c_ru_.

39. 10. Which color of light
has the longest
wavelength and carries
lesser energy?