Question

A point mass is subjected to two simultaneous sinusoidal displacements in `x - direction, x_1 (t) = A sin (omega)t and x_2 (t) = A sin ((omega t + (2 pi)/(3))`. Adding a third sinusoidal displacement `x _3 (t) = B sin (omega t + phi)` brings the mas to a complete rest. The values of (B) and (phi) are.
A. `sqrt(2) A, (3 pi)/(4)`
B. `A, (4 pi)/(3)`
C. `sqrt(3) A, (5 pi)/(6)`
D. `A, (pi)/(3)`

Answer 1

Correct Answer - B
So, `B = A, phi = 240^@ = (4 pi)/(3)`.
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