# Three waves of equal frequency having amplitudes  arrive at a given point with successive phase difference of , the amplitude of the resulting wave in  is given by

## Question ID - 150082 :- Three waves of equal frequency having amplitudes  arrive at a given point with successive phase difference of , the amplitude of the resulting wave in  is given by

3537

Answer Key : (5) -

The amplitudes of the waves are

and

and the phase difference between 1st and 2nd wave is  and that between 2nd and 3rd is . Therefore, phase difference between 1st and 3rd is . Combining 1st with 3rd, their resultant amplitude is given by

Or

in the direction of first

Now combining this with 2nd wave we have, the resultant amplitude

Or

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