CHAPTER 7. TRANSVERSE PULSES 7.3
pulses move towards each otherpulses constructively interferepulses move away from otherpulses move towards each otherpulses constructively interferepulses move away from otherFigure 7.3: Superposition of two pulses: constructive interference.Destructive interference takes place when two pulses meet and result in a smaller ampli-
tude disturbance. The amplitude of the resulting pulse is the sum of the amplitudes of
the two initial pulses, but the one amplitude will be a negative number. This is shown in
Figure 7.4. In general, amplitudes of individual pulses are summed together to give the
amplitude of the resultant pulse.
DEFINITION: Destructive interference
Destructive interference is when two pulses meet, resulting in a smaller
pulse.pulses move towards each otherpulses destructively interferepulses move away from otherpulses move towards each otherpulses interferepulses move away from otherFigure 7.4: Superposition of two pulses. The left-hand series of images demonstrates de-
structive interference, since the pulses cancel each other. The right-hand series of images
demonstrate a partial cancellation of two pulses, as their amplitudes are not the same in
magnitude.
Physics: Waves, Sound and Light 131