JEE Mains · Physics · STD 12 - Moving charges and magnetism
- JEE Mains 2015
- Hard
- MCQ
A proton (mass \(m\) ) accelerated by a potential difference \(V\) flies through a uniform transverse magnetic field \(B.\) The field occupies a region of space by width \('d'\). If \(\alpha \) be the angle of deviation of proton from initial direction of motion (see figure), the value of \(sin\,\alpha \) will be

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(Bd\sqrt {\frac{q}{{2mV}}} \)
Step-by-step Solution
Detailed explanation
From figure, \(sin\,\alpha =dlR\)
And we know, \(\frac{m v^{2}}{R}=q v B\)
\(\Rightarrow \quad R=\frac{m v}{q B}\)
\(\because \sin \alpha=\frac{d q B}{m v}\)
\(\sin \alpha=B d \sqrt{\frac{q}{2 m V}}\left[\because q V=\frac{1}{2} m v^{2}\right]\)
More questions from Physics
- In \(Li^{++},\) electron in first Bohr orbit is excited to a level by a radiation of wavelength \(\lambda .\) When the ion gets deexcited to the ground state in all possible ways(including intermediate emission) a total of six spectral lines are observed. What is the value of \(\lambda \)?.....\(nm\) (Given: \(h = 6.63\times 10^{34}\,js; e = 3 \times 10^8\,ms^{-1}\) )JEE Mains 2019 Hard
- A cube has side length \(5\) cm and modulus of rigidity \(10^5\) N/m\(^2\). The displacement produced by a force of \(10\) N in the upper face of cube is _____ mm.JEE Mains 2026 Medium
- The electric flux is \(\phi=\alpha \sigma+\beta \lambda\) where \(\lambda\) and \(\sigma\) are linear and surface charge density, respectively. \(\left(\frac{\alpha}{\beta}\right)\) representsJEE Mains 2025 Easy
- Light travels in two media \(M _{1}\) and \(M _{2}\) with speeds \(1.5 \times 10^{8} ms ^{-1}\) and \(2.0 \times 10^{8} ms ^{-1}\) respectively. The critical angle between them is.JEE Mains 2022 Medium
- A photograph of a landscape is captured by a drone camera at a height of 18 km . The size of the camera film is \(2 \mathrm{~cm} \times 2 \mathrm{~cm}\) and the area of the landscape photographed is \(400 \mathrm{~km}^2\). The focal length of the lens in the drone camera is :JEE Mains 2025 Easy
- Two ideal diodes are connected in the network as shown in figure. The equivalent resistance between \(A\) and \(B\) is \(.......\Omega\).
JEE Mains 2022 Medium
More PYQs from JEE Mains
- There is a circular tube in a vertical plane. Two liquids which do not mix and of densities \(d_1\) and \(d_2\) are filled in the tube. Each liquid subtends \(90^o\) angle at centre. Radius joining their interface makes an angle \(\alpha\) with vertical. Ratio \(\frac{{{d_1}}}{{{d_2}}}\) is
JEE Mains 2014 Hard - Two liquids of densities \(\rho_{1}\) and \(\rho_{2}\left(\rho_{2}=2 \rho_{1}\right)\) are filled up behind a square wall of side \(10\; \mathrm{m}\) as shown in figure. Each liquid has a height of \(5 \;\mathrm{m} .\) The ratio of the forces due to these liquids exerted on upper part \(MN\) to that at the lower pait \(NO\) is (Assume that the liquids are not mixing)
JEE Mains 2020 Medium - In an electrical circuit drawn below the amount of charge stored in the capacitor is _______ \(\mu \mathrm{C}\).
JEE Mains 2024 Hard