In the adjacent diagram, CP represents a wavefront and AO & BP, the corresponding two rays. Find the condition on θ for constructive interference at P between the ray BP and reflected ray OP

1. cosθ=3λ/2d

2. cosθ=λ/4d

3. secθ-cosθ=λ/d

4. secθ-cosθ=4λ/d

Please attempt this question first.
Hints

In Young's double slit experiment with slit seperation d, a monochromatic light of wavelength λ is used. The angular seperation of the fringes is

1. d/λ

2. λ/d

3. 2λ/d

4. λ/2d

PMT - 2012
Please attempt this question first.
Hints

Two slits in Young's experiment have widths in the ratio 1:25. The ratio of intensity at the maximum and minimum in the interferance pattern, ImaxImin is

1. 12149

2. 49121

3. 49

4. 94

AIPMT - 2015
Please attempt this question first.
Hints

advertisementadvertisement

At the first minimum adjacent to the central maximum of a single-slit differaction pattern, the phase difference between the Huygen's wavelet from the edge of the slit and the wavelet from the midpoint of the slit is

1. π2radian 

2. π radian

3. π8 radian

4. π4radian

AIPMT - 2015
Please attempt this question first.
Hints

Two beams of light will not give rise to an interference pattem, if

1. They are coherent

2. They have the same wavelength

3. They are linearly polarized perpendicular to each other

4. They are not monochromatic

Please attempt this question first.
Hints

Young's experiment is performed in air and then performed in water, the fringe width 

1. Will remain same

2. Will decrease

3. Will increase

4. Will be infinite

 60%
PMT - 1997
Please attempt this question first.
Hints

advertisementadvertisement

In the Young's double slit experiment, if the phase difference between the two waves interfering at a point is ϕ, the intensity at that point can be expressed by the expression

1. l=A2+B2 cos2ϕ

2. I=ABcosϕ

3. I=A+B cosϕ2

4. I=A+B cosϕ

Where A and B depend upon the amplitude of the two waves.

PMT - 2003
Please attempt this question first.
Hints

A slit of width a is illuminated by white light. For red light λ=6500A°, the first minima is obtained at θ=30°. Then the value of a will be 

1. 3250 A°

2. 6.5×10-4 mm

3. 1.24 microns

4. 2.6×10-4 cm

PMT - 2002
Please attempt this question first.
Hints

Two waves originating from source S1 and S2 having zero phase difference and common wavelength λ will show completely destructive interference at a point P if S1P-S2P is

1. 5λ

2. 3λ / 4

3. 2λ

4. 11λ / 2

Please attempt this question first.
Hints

advertisementadvertisement

The Brewster angle for the glass-air interface is 54.74o. lf a ray of light going from air to glass strikes at an angle of incidence 45o, then the angle of refraction is

(Hint: tan 54.74= 2)

1. 60o

2. 30o

3. 25o

4. 54.74o

Please attempt this question first.
Hints