Page 180 - text book form physics kssm 2020

Direction of transfer of energy
Movement of waves from end A to end B
Movement of ribbon transfers energy from A to B.

Ribbon Th e ribbon only vibrates about in a fi xed position.
A B
Th e ribbon does not move in the direction in
which the energy is transferred by the waves.

Figure 5.4 Waves transfer energy without
transferring matter
Wave profile moving to the right
Types of Waves Direction of propagation

Figure 5.5 shows the shape of the slinky spring
at fi ve consecutive instances aft er end A has been t 1
moved as in Activity 5.2. Th e shape of the slinky End A End B
spring as waves propagate through it is known as t
wave profi le. 2

Waves can be classifi ed from the aspect of t
propagation of the wave profi le. Th e wave profi le 3
in Figure 5.5 propagates with time along the
direction of propagation of the wave. Th is wave is t 4
known as a progressive wave.
t
Photograph 5.3 shows an example of a 5
progressive wave produced by the vibrations on
the surface of the water. A wave profi le propagates Figure 5.5 Wave profi le at fi ve consecutive
outwards in all directions. instances

Video of progressive wave
on surface of water

http://bt.sasbadi.com/p4174a

Transverse waves and
longitudinal waves
Photograph 5.3 Progressive waves on the water surface
Progressive waves can propagate through a medium as
transverse waves or longitudinal waves. Scan the QR code to
http://bt.sasbadi.com/p4174b
watch the animation of transverse waves and longitudinal
waves.
174
174 5.1.1 5.1.2
174
174
5.1.2
5.1.1