MCQ
How will the diffraction pattern change when yellow light is replaced by blue light? The fringe will be :-
- AWider
- ✓Narrower
- CBrighter
- DFainter
✓
Answer
Correct option: B.
Narrower
b
$\because \theta=\frac{\lambda}{a} \Rightarrow \theta \propto \lambda$
$\because \theta=\frac{\lambda}{a} \Rightarrow \theta \propto \lambda$
and $\lambda_{\mathrm{B}}<\lambda_{\mathrm{y}}, \mathrm{So}, \theta_{\mathrm{B}}<\theta_{\mathrm{y}}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains helium (monoatomic), the second contains fluorine (diatomic) and the third contains sulfur hexafluoride (polyatomic). The correct statement, among the following is
The harmonics which are present in a pipe open at one end are
The positions of four different nuclei in the binding energy curve are shown in figure. The process that might not proceed spontaneously is
Column $I$ gives some devices and Column $II$ gives some process on which the functioning of these devices depend. Match the devices in Column $I$ with the processes in Column $II$ and indicate your answer by darkening appropriate bubbles in the $4 \times 4$ matrix given in the $ORS$.
→| Column $I$ | Column $II$ |
| $(A)$ Bimetallic strip | $(p)$ Radiation from a hot body |
| $(B)$ Steam engine | $(q)$ Energy conversion |
| $(C)$ Incandescent lamp | $(r)$ Melting |
| $(D)$ Electric fuse | $(s)$ Thermal expansion of solids |
An $\alpha$ particle and a carbon $12$ atom has same kinetic energy $K$. The ratio of their de-Broglie wavelength $\left(\lambda_{a}: \lambda_{C 12}\right)$ is
→A man sitting in a moving train hears the whistle of the engine. The frequency of the whistle is $600 Hz$
→$A$ concave mirror is placed on a horizontal surface and two thin uniform layers of different transparent liquids (which do not mix or interact) are formed on the reflecting surface. The refractive indices of the upper and lower liquids are $\mu_1$ and $\mu_2$ respectively. The bright point source at a height $‘d’$ ($d$ is very large in comparison to the thickness of the film) above the mirror coincides with its own final image. The radius of curvature of the reflecting surface therefore is
→A crystal diode is a
A motor cyclist going round in a circular track at constant speed has
The moment of inertia of semicircular plate of radius $R$ and mass $M$ about axis $AA’$ in its plane passing through its centre is
→