IIT JEE , AIEEE Forum - Physics , Mechanics

Mr.IITIAN007

Two waves y₁ = A₁sin omega ₁ t and y₂ = A₂sin omega ₂ t superimpose to form a resultant wave . What is the amplitude of that resultant wave ?

phyana

hey iit2007.................i didnt gt what u have written in the brackets..........................

any way method is simple...............
u have to convert the second wave eq into cos by addiong a additional phas of 90
add the two wave equation.
u get two expression in sin form with a constant a1,a2 in the expression.in that case divide and multiply with sqtroot(a1^2 +a2^2)

put a1 / sqtroot(a1^2 +a2^2) = coa (alpha)
a2/ sqtroot(a1^2 +a2^2)= sin alpha

now it would be in the form
which can be reduced again.............

thus u get the amplitude as sqtroot(a1^2 +a2^2)

rohil

errrr when 2 waves of different frequencies superimpose, it doesnt make a travelling wave i think. Its like 2 SHM superimposing. When 2 SHMs of different frequencies superimpose, the resultant is not a SHM, its a PERIODIC motion but not SHM. Same here. Here, resultant wont be a normal sine travelling wave.

phyana

i explained the answer...........assuming that the frequency is same....................

if the frequency is different then then it give rise to lisajous figures...............

for example if phase diff =90 then a circle will be obtained

rate me plz...............if u plz

devesh_l2k007

y u ppl r makin a mess of things

Wen 2 waves of diff amp but same frequency superimpose res is interfernce

As in this prob the phase diff is zero hence amp is A1+ A2

@rohil : refer page 1 module 7 physics

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