Two identical sinusoidal waves, moving in same direction along a stretched string, interfere, with each other. The amplitude of each wave is 10.0mm, and the phase difference between them is `80^(@)`. What is the amplitude of the resultant wave and the nature of interference ?

Explanation

Here, amplitude of each wave `a=b=10mm`
phase difference `=phi=80^(@)`
The amplitude of resultant wave is,
`R=sqrt(a^(2)+b^(2)+2abcosphi)`
`=sqrt(10^(2)+10^(2)+2xx10xx10cos80^(@))`
`=sqrt(100+100+200xx0.1736)`
`=sqrt(234.72)=15.32mm`