Intensity Amplitude Relationship

Q. A parallel beam of sodium light of wavelength 589 nm is incident at an angle of 30° on the film of olive oil ( μ= 1.6) on water. Calculate the smallest thickness of the film which will make it appear dark.

Q. what is wave equation ? Asin (wt-kx+fi) OR Asin (kx +/-wt +/- fi)

Q. How to represent wave equation

Q. in a single slit diffraction light of wavelength 6000 A is used and the screen is 50 cm away from slit . if distance between the first and third minima is 3mm , then width of the slit is (1) 0.15 mm (2) 0.20 mm (3) 0.25 mm (4) 0.3 mm

Q. What are wave equations, how to represent wave equation in a circle

Q. How to write wave equation

Q. Two beams of light having intensities $I$ and $4I$ interfere to produce a fringe pattern on a screen. The phase difference between the beams is $\frac{\pi }{2}$ at point $A$ and $2\pi$ at point $B$. Then the difference between the resultant intensities at $B$ and $A$ will be

1. $4I$
2. $3I$
3. $I$
4. $5I$

Q.

Two coherent sources of intensity ratio $\beta$ interfere. Find the ratio $\frac{[I_{max}-I_{min}]}{[I_{max}+I_{min}]}$ in the interference pattern.

1. $\frac{2\sqrt{\beta }}{[1+\beta ]}$
2. $\frac{2\beta }{[1+\beta ]}$
3. $\left[\frac{(\sqrt{\beta }+1)}{(\sqrt{\beta }-1)}\right]$

4. $\frac{\sqrt{\beta }}{(1+\sqrt{\beta })}$

Q. A String fixed at both ends has consecutive s†an ding wave modes for which the separation between two successive nodes are 18 cm and 16 cm respectively. then find the maximum possible length of the string ( how to dothis?)

Q. In Lloyd's mirror experiment, a light wave emitted directly by the source $S\left(\text{narrow slit}\right)$ interferes with the wave reflected from a mirror $M$. As a result, an interference fringe pattern is formed on the screen which is $1\text{m}$ far from mirror. The source and the mirror are separated by a distance $l=100\text{cm}$. At a certain position of the source, the fringe width on the screen was equal to $\beta =0.25\text{mm}$ and after the source was moved away from the mirror plane by $\Delta h=0.60\text{mm}$ the fringe width decreased by $1.5\text{times}$. Find the wavelength of light from the source.

1. $0.2\mu \text{m}$
2. $0.6\mu \text{m}$
3. $1\mu \text{m}$
4. $0.4\mu \text{m}$

Q. A glass plate of thickness $t$ is placed in front of one of the slits in a Young's double slit experiment. It is found that the interference pattern is shifted through a distance $d$. If this whole setup is immersed in water, the shift in pattern will be:
$[\text{Given: Refractive index of glass,}{\mu }_g=\frac{3}{2},\text{Refractive index of water}{\mu }_w=\frac{4}{3}]$

1. $\frac{d}{2}$
2. $4d$
3. $2d$
4. $\frac{d}{4}$

Q. Show wave equations for different waves

Q. What is meant by applying boundary conditions on a stationary wave equation ?

Q. A parallel beam of monochromatic light of wavelength 450nm passes through a slit of width 0.2 mm. The angular divergence is?