is d ans 98 fr 2nd one??????????
The equations of 2 waves r,
y1=acos(0.5Ï€x-100Ï€t)
y2=acos(0.46Ï€x-92Ï€t).
Find:
(i)Number of times intensity is max in a time interval of 1 sec.
(ii)No. of times y1+y2=0 at x=0 in 1 sec.
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UP 0 DOWN 0 0 12
12 Answers
can u post the answers ............. if my ans maches ill post soln.
y1 + y2 is net disp of wave...................
acos(0.5pi x - 100pi t ) + acos(0.46pi x - 92 pi t)
2acos(96 pi t)cos(4 pi t) <--[edited calc error here]
y1 + y2 = 0 if and only if one of the angles are of form (2n+1)pi/2 ... n E N
96pi t = (2n+1)pi/2
192 t = 2n + 1
t = (2n + 1) /(384)
= n/96 + 1/192
let it be in interval 0-1 ....
191/192 = n/96
191/2 = n
[191/2] = 95 times....................
4 t = (2n+1)/2
t = n/4 + 1/8 .........................
[7/2] = 3
98 it is sorry for that trivial mistake
correct if rong ..........
@ iit comin
acos(0.5pi x - 100pi t ) + acos(0.46pi x - 92 pi t)
at x =0
acos(100pi t ) + acos(92 pi t)
2acos(192 pi t)cos(8 pi t) /// error
and for maxima ... put n pi
shud be satisfy both the cos functions simultaneously ,,,,
oh... its 192/2 , 8/2 inside the cos sorry .....see post 6 for corrected soln.