JEE Mains · Physics · STD 12 - Wave optics
- JEE Mains 2024
- Hard
- MCQ
In Young's double slit experiment, light from two identical sources are superimposing on a screen. The path difference between the two lights reaching at a point on the screen is \(\frac{7 \lambda}{4}\). The ratio of intensity of fringe at this point with respect to the maximum intensity of the fringe is _______.
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(1 / 2\)
Step-by-step Solution
Detailed explanation
\( \Delta \mathrm{x}=\frac{7 \lambda}{4} \)
\( \phi=\frac{2 \pi}{\lambda} \Delta \mathrm{x}=\frac{2 \pi}{\lambda} \times \frac{7 \lambda}{4}=\frac{7 \pi}{2} \)
\( \mathrm{I}=\mathrm{I}_{\max } \cos ^2\left(\frac{\phi}{2}\right) \)
\( \frac{\mathrm{I}}{\mathrm{I}_{\max }}=\cos ^2\left(\frac{\phi}{2}\right)=\cos ^2\left(\frac{7 \pi}{2 \times 2}\right)=\cos ^2\left(\frac{7 \pi}{4}\right) \)
\(=\cos ^2\left(2 \pi-\frac{\pi}{4}\right) \)
\(=\cos ^2 \frac{\pi}{4} \)
\(=\frac{1}{2}\)
More questions from Physics
- A uniform rod of mass m and length \(l\) suspended by means of two identical inextensible light strings as shown in figure. Tension in one string immediately after the other string is cut, is _________.(g acceleration due to gravity)
JEE Mains 2026 Easy - A student determined Young's Modulus of elasticity using the formula \(Y=\frac{M g L^{3}}{4 b d^{3} \delta} .\) The value of \(g\) is taken to be \(9.8 \,{m} / {s}^{2}\), without any significant error, his observation are as following.
Then the fractional error in the measurement of \({Y}\) isPhysical Quantity Least count of the Equipment used for measurement Observed value Mass \(({M})\) \(1\; {g}\) \(2\; {kg}\) Length of bar \((L)\) \(1\; {mm}\) \(1 \;{m}\) Breadth of bar \((b)\) \(0.1\; {mm}\) \(4\; {cm}\) Thickness of bar \((d)\) \(0.01\; {mm}\) \(0.4 \;{cm}\) Depression \((\delta)\) \(0.01\; {mm}\) \(5 \;{mm}\) JEE Mains 2021 Hard - The position vector of a particle related to time \(t\) is given by \(\overrightarrow{ r }=\left(10 t \hat{ i }+15 t ^2 \hat{ j }+7 \hat{ k }\right) m\) The direction of net force experienced by the particle isJEE Mains 2023 Medium
- Two resistors of \(100 \Omega\) each are connected in series with a 9 V battery. A voltmeter of \(400 \Omega\) resistance is connected to measure the voltage drop across one of the resistors. The voltmeter reading is _________ V.JEE Mains 2026 Easy
- An object with mass 500 g moves along x -axis with speed \(v=4 \sqrt{x} \mathrm{~m} / \mathrm{s}\). The force acting on the object is :JEE Mains 2025 Easy
- A current of \(30\) A each flows in opposite directions in two conducting wires, placed parallel to each other at a distance of \(8\) cm. The magnetic field at the mid point between the two wires is __________ \(\mu\)T. \(\left(\dfrac{\mu_0}{4\pi} = 10^{-7}\text{ N/A}^2\right)\)JEE Mains 2026 Medium
More PYQs from JEE Mains
- Surface tension of two liquids (having same densities), \(T_1\) and \(T_2\), are measured using capillary rise method utilizing two tubes with inner radii of \(r_1\) and \(r_2\) where \(r_1>r_2\). The measured liquid heights in these tubes are \(h_1\) and \(h_2\) respectively. [Ignore the weight of the liquid about the lowest point of miniscus]. The heights \(h _1\) and \(h _2\) and surface tensions \(T _1\) and \(T _2\) satisfy the relation :JEE Mains 2026 Easy
- A particle is executing simple harmonic motion with time period 2 s and amplitude 1 cm . If D and d are the total distance and displacement covered by the particle in 12.5 s , then \(\frac{\mathrm{D}}{\mathrm{d}}\) is ________.JEE Mains 2025 Easy
- Given below are two statements: Statement \(I :\) In a diatomic molecule, the rotational energy at a given temperature obeys Maxwell's distribution. Statement \(II :\) In a diatomic molecule, the rotational energy at a given temperature equals the translational kinetic energy for each molecule. In the light of the above statements, choose the correct answer from the options given below:JEE Mains 2021 Medium
- The equation for real gas is given by \(\left(\mathrm{P}+\frac{\mathrm{a}}{\mathrm{V}^2}\right)(\mathrm{V}-\mathrm{b})=\mathrm{RT}\), where \(\mathrm{P}, \mathrm{V}, \mathrm{T}\) and R are the pressure, volume, temperature and gas constant, respectively. The dimension of \(\mathrm{ab}^{-2}\) is equivalent to that of :JEE Mains 2025 Medium
- Calculate the value of mean free path \((\lambda)\) for oxygen molecules at temperature \(27^{\circ}\, C\) and pressure \(1.01 \times 10^{5} \,Pa\). Assume the molecular diameter \(0.3 \,nm\) and the gas is ideal. \(\left( k =1.38 \times 10^{-23}\, J\,K ^{-1}\right)\) (in \(nm\))JEE Mains 2021 Hard