SHMHard
Question
Three simple harmonic motion in the same direction having the same amplitude and same period are suspended. If each differ in phase from the next by 45o, then
Options
A.the resultant amplitude is ( 1 + √2)α
B.the phase of the resultant motion relative to the first is 90o
C.the energy associated with the resulting motion is (3 + 2 √2) times the energy associated with any single motion
D.(d) the resulting motion is not simple harmonic
Solution
From superposition priciple
y = y1 + y2 + y3
= a sin ωt + a sin (ωt + 45o) + a sin (ωt + 90o)
= a[ sin ωt + sin (ωt + 90o)] + a sin (ω + 45o)
= 2a sin (ωt + 45o) cos 45o + a sin (ωt + 45o)
= (√2 + 1) a sin (ωt + 45o) = A sin (ωt + 45o)
Therefore, resultant motion is simple harmonic of amplitude
A = (√2 + 1)a
and which differ in phase by 45o relative to the first.
Energy in SHM ∝ (amplitude)2 [E =
mA2 ω2]
∴
=
= (√2 + 1)2 = (3 + 2√2)
∴ Eresultant = (3 + 2√2) Esingle
y = y1 + y2 + y3
= a sin ωt + a sin (ωt + 45o) + a sin (ωt + 90o)
= a[ sin ωt + sin (ωt + 90o)] + a sin (ω + 45o)
= 2a sin (ωt + 45o) cos 45o + a sin (ωt + 45o)
= (√2 + 1) a sin (ωt + 45o) = A sin (ωt + 45o)
Therefore, resultant motion is simple harmonic of amplitude
A = (√2 + 1)a
and which differ in phase by 45o relative to the first.
Energy in SHM ∝ (amplitude)2 [E =
mA2 ω2]∴
=
= (√2 + 1)2 = (3 + 2√2)∴ Eresultant = (3 + 2√2) Esingle
Create a free account to view solution
View Solution FreeMore SHM Questions
A pendulum isA pendulum is suspended in a lift and its period of oscillation when the lift is stationary is T0. What mus...The time period of a particle exciting SHM is T. after a time T/6 after it passes its :...The bob of a simple pendulum is a spherical hollow ball filled with water. A plugged hole near the bottom of the oscilla...A ball is hung vertically by a thread of length ′l′ from a point ′P′ of an inclined wall that ma...A 25 kg uniform solid sphere with a 20 cm radius is suspended by a vertical wire such that the point of suspension is ve...