MCQ
In Young's double slit experiment, if the separation between coherent sources is halved and the distance of the screen from the coherent sources is doubled, then the fringe width becomes:
- Aone$-$fourth
- Bdouble
- Chalf
- ✓four times
✓
Answer
Correct option: D.
four times
d
$\beta=\frac{\lambda D}{d}$
$\beta=\frac{\lambda D}{d}$
$\beta^{\prime}=\frac{\lambda D^{\prime}}{d^{\prime}}$
$D ^{\prime}=2 D , d ^{\prime}=\frac{ d }{2}$
$\beta^{\prime}=\frac{\lambda \times 2 D}{d / 2}=\frac{4 \lambda D}{d}$
$\beta^{\prime}=4 \beta$
Fringe with becomes $4$ times
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
In capillary pressure below the curved surface of water will be
A polyatomic gas with six degrees of freedom does $25\,\,J$ of work when it is expanded at constant pressure. The heat given to the gas is ..... $J$
→Three processes form a thermodynamic cycle as shown on $P-V$ diagram for an ideal gas. Process $1 \rightarrow 2$ takes place at constant temperature $(300K$). Process $2 \rightarrow 3$ takes place at constant volume. During this process $40J$ of heat leaves the system. Process $3 \rightarrow 1$ is adiabatic and temperature $T_3$ is $275K$. Work done by the gas during the process $3 \rightarrow 1$ is ..... $J$
→If each diode has a forward bias resistance of $25\,\Omega$ in the below circuit,Which of the following options is correct:
→The temperature of a liquid drops from $365K$ to $361 K$ in $2$ minutes. Find the time during which temperature of the liquid drops from $344\;K$ to $342K$. Temperature of room is $293\;K$ ....... $\sec$
→A thin hollow cylinder open at both ends:
→$(i)$ Slides without rotating
$(ii)$ Rolls without slipping, with the same speed
Ionisation energy of $Li$ (Lithium) atom in ground state is $5 .4\,eV. $ Binding energy of an electron in $Li^+$ ion in ground state is $75.6\,eV.$ Energy required to remove all three electrons of Lithium $(Li)$ atom is ........... $eV$
→The force acting on a body moving along $x-$axis varies with the position of the particle as shown in the fig.The body is in stable equilibrium at
→Two trains are moving with equal speed in opposite directions along two parallel railway tracks. If the wind is blowing with speed $u$ along the track so that the relative velocities of the trains with respect to the wind are in the ratio of $1:2$, then the speed of each train must be
→A $NCC$ parade is going at a uniform speed of $9\,km / h$ under a mango tree on which a monkey is sitting at a height of $19.6\,m$. At any particular instant, the monkey drops a mango. A cadet will receive the mango whose distance from the tree at time of drop is $...m$
→(Given $g=9.8\,m / s ^{2}$ )