MCQ
In a Young’s double slit experiment, the path difference, at a certain point on the screen, between two interfering waves is $1/8^{th}$ of wavelength. The ratio of the intensity at this point to that at the centre of a bright fringe is close to
  • A
    $0.74$
  • $0.85$
  • C
    $0.94$
  • D
    $0.80$

Answer

Correct option: B.
$0.85$
b
$\Delta x=\frac{\lambda}{8}$

Phase $|\Delta P|=\frac{2 \pi}{\lambda} \times \frac{\lambda}{8}=\frac{\pi}{4}$

$\therefore $ $\mathrm{I}_{\mathrm{res}}=I+I+2I \cos \left(\frac{\mathrm{R}}{4}\right)$

$=\,2I\left(1+\frac{1}{\sqrt{2}}\right)=2I \times 1.7$

$\therefore \quad \frac{I_{res }}{I_{\operatorname{man}}}=\frac{2I\times 1.7}{41}=0.85$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

With a change of load resistance of a triode, used as an amplifier, from $50 \,kilo\, ohms$ to $100 \,kilo \,ohms$, its voltage amplification changes from $25$ to $30$. Plate resistance of the triode is.....$k\, \Omega$
When two resistance $R_1$ and $R_2$ connected in series and introduced into the left gap of a meter bridge and a resistance of $10 \Omega$ is introduced into the right gap, a null point is found at $60 cm$ from left side. When $R_1$ and $R_2$ are connected in parallel and introduced into the left gap, a resistance of $3 \Omega$ is introduced into the right-gap to get null point at 40 cm from left end. The product of $R_1 R_2$ is $.............\Omega$
Switch $S$ of the circuit shown in figure. is closed at $t = 0$. If e denotes the induced emf in $L$ and i, the current flowing through the circuit at time $t $, which of the following graphs is correct
In the case of constants $\alpha$ and $\beta$ of a transistor
Work function of a metal is $2.1 eV$. Which of the waves of the following wavelengths will be able to emit photoelectrons from its surface
With the rise in temperature, the dielectric constant $K$ of a liquid
If the frequency of light in a photoelectric experiment is doubled, the stopping potential will:
All of the following statements are correct except
The average $e.m.f$. induced in a coil in which a current changes from $0$ to $2 \,A$ in $0.05$ $s$ is $8 \,V.$ The self inductance of the coil is....$H$
Consider an initially pure $M$ gm sample of$_ A{X}$, an isotope that has a half life of $T$ hour, what is it’s initial decay rate ($N_A$ = Avogrado No.)