A planar cross section through two spherical waves emanating from the sources S1 and S2 in the plane is shown in the figure. The black circles are one and two wavelengths from their respective sources. The lighter circles are one half and one and a half wavelengths distant from their respective sources. If the phase at S1 and S2 is zero at this instant, and the waves shown arriving at P1 both arrive with amplitude A, the magnitude of the phase angle of each wave at point P1 (in radians) is

a.
0.
b.
.
c.
2
.
d.
3
.
e.
/2.
Question 2A planar cross section through two spherical waves emanating from the sources S1 and S2 in the plane is shown in the figure. S1 and S2 are in phase. The black circles are one and two wavelengths from their respective sources. The lighter circles are one half and one and a half wavelengths distant from their respective sources. If the waves shown arriving at P2 both arrive with amplitude A, the resultant amplitude at point P2 is

a.
0.
b.

.
c.
A.
d.

.
e.
2
A.