A monochromatic light source of wavelength `lamda` is placed at S. three slits `S_(1),S_(2)` and `S_(3)` are equidistant from the source S and the point P on the screen `S_(1)P-S_(2)P=lamda//6` and `S_(1)P-S_(3)P=2lamda//3`. if I be the intensity at P when only one slit is open the intensity at P when all the three `slits` are open is-

In the figure shown S_(1)O-S_(2)O=S_(3)O-S_(2)O=(lambda)/(4) , Intensity at O due to any one of the slits is I_(0) . What is the intensity due to all the three coherent sources S_(1), S_(2) and S_(3) ?

Two sound waves each of wavelength lamda and having the same amplitude A form two sources S_(1) and S_(2) interfere at a point P. If the path difference S_(2)P - S_(1)P = (lamda)/(3) , then the amplitude of the resultant were at P will be

In arrangement shown in figure, plane wavefront of monochromatic light of wavelength lamda is incident on identical slits S_(1) and S_(2) . There is another pair of indentical slits S_(3) and S_(4) which are having separation Z = (lamda D)/(2d) Point O is on the screen at the common perpendicular bisector of S_(1)S_(2) and S_(3) S_(4).I_(1) is the intensity at point O Now the board having slits S_(3)S_(4) is moved upward parallel to itself and perpendicular to line AO till slit S_(4) is on line AO and it is observed that now intensity at point O is I_(2) then (I_(2))/(I_(1)) is :

In arrangement shown in figure, plane wavefront of monochromatic light of wavelength lamda is incident on identical slits S_(1) and S_(2) . There is another pair of indentical slits S_(3) and S_(4) which are having separation Z = (lamda D)/(2d) Point O is on the screen at the common perpendicular bisector of S_(1)S_(2) and S_(3) S_(4).I_(1) is the intensity at point O Now the board having slits S_(3)S_(4) is moved upward parallel to itself and perpendicular to line AO till slit S_(4) is on line AO and it is observed that now intensity at point O is I_(2) then (I_(2))/(I_(1)) is :

In a young's doule slits experiment, a monochromatic source of wavelength lambda is used to illuminate the two slits S_(1) and S_(2) . The slitss S_(1) and S_(2) are identical and source S is placed symmetrically as shown. interference pattern is observed on a screen at a distance D from the centre of slit. The distance between the slits is d. If the resultant intensity at P is same as that O, then the distance OP can not be

In the case of light waves from two coherent sources S_(1) and S_(2) , there will be constructive interference at an arbitrary point P, the path difference S_(1)P - S_(2)P is