MCQ
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 \left(\omega t+\frac{2 \pi}{3}\right)$. Adding a third sinusoidal displacement $x_3(t)=B \sin (\omega t+\phi)$ brings the mass to a complete rest. The values of $B$ and $\phi$ are
- A$\sqrt{2} A, \frac{3 \pi}{4}$
- ✓$A, \frac{4 \pi}{3}$
- C$\sqrt{3} A, \frac{5 \pi}{6}$
- D$A, \frac{\pi}{3}$
