PHYSICS - 1ST SECONDARY

1. 7.5
DISPERSION AND SPECTRUM

2. Splitting White Light
 The component colours of white light can
be separated using refraction.
 Each colour refracts a slightly different
amount and so colours spread out slightly
 This effect is called ((Dispersion))
2

3. Dispersion
Splitting of white light into
component colours using
refraction through a glass prism
3

4. “The Prism ”
1- is used to disperse light .
The light refracts twice and this helps
to spread out the colours so they can be
seen more easily
2- is used to clarify light refraction
4

5. “The Prism ”
5

6. What is the composition of white light?
• A white light is made up of seven different colours which can be
seen clearly after the dispersion of white light through the
GLASS PRISM
• The seven colours are :
RED –ORANGE – YELLOW – GREEN – BLUE – INDIGO –VIOLET
• The continuous range of colours produced is known as
SPECTRUM
6

7. IN RAINBOWS 7
Passing the light of the sun
through tiny droplets of
water .These droplets act as
tiny prisms. The colours of
the spectrum are separated
out producing rainbow
effect
Rainbows are
formed as a
result of

8. Questions
8

9. Q1- What would happen if you tried to use a prism to disperse:
i- a beam that contained only green light
ii- a beam of white light
9
😉

10. 10
😉
Q2- This diagram shows two prisms being used to
investigate dispersion. The first prism separates out the
colours , the second recombines them .Copy and complete
the diagram labelling the colours of light including the final
colour?

11. 11
😉
Q 3

12. SIR.MUHAMMAD ABDUL MAGEID