enEnglishguગુજરાતી
JEE Mains · Physics · STD 12 -Electromagnetic induction
- JEE Mains 2023
- Medium
- Numerical
A \(1\,m\) long metal rod \(XY\) completes the circuit as shown in figure. The plane of the circuit is perpendicular to the magnetic field of flux density \(0.15\,T\). If the resistance of the circuit is \(5\,\Omega\), the force needed to move the rod in direction, as indicated, with a constant speed of \(4\,m / s\) will be \(................\,10^{-3}\,N\)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(18\)
Step-by-step Solution
Detailed explanation
\(F = i \ell B\)
\(=\left(\frac{\varepsilon}{ R }\right) \ell B =\left(\frac{ vB \ell}{ R }\right) \ell B =\frac{ vB ^2 \ell^2}{ R }=\frac{4}{5} \times\left(\frac{15}{100}\right)^2 \times 1^2\)
\(=\frac{4}{5} \times \frac{225}{10^4}\)
\(=\frac{180}{10^4}=0.018\,N\)
\(=18 \times 10^{-3}\,N\)
More questions from Physics
- As shown in figure, when a spherical cavity (centred at \(\mathrm{O})\) of radius \(1\) is cut out of a uniform sphere of radius \(\mathrm{R} \text { (centred at } \mathrm{C}),\) the centre of mass of remaining (shaded) part of sphere is at \(G\), i.e, on the surface of the cavity. \(\mathrm{R}\) can be detemined by the equation
JEE Mains 2020 Hard - Five equal resistances are connected in a network as shown in figure. The net resistance between the points \(A\) and \(B\) is
JEE Mains 2021 Medium - A gas based geyser heats water flowing at the rate of 5.0 litres per minute from \(27^{\circ} C\) to \(87^{\circ} C\).
The rate of consumption of the gas is ___________ \(g / s\).
(Take heat of combustion of gas \(=5.0 \times 10^4 J / g\) ) specific heat capacity of water \(=4200 J / kg.~{ }^{\circ} C\)JEE Mains 2026 Easy - The time period of a satellite in a circular orbit of radius \(R\) is \(T\). The period of another satellite in a circular orbit of radius \(9 R\) is............ \(T\)JEE Mains 2021 Medium
- A particle of mass \('{m}'\) is moving in time \('t'\) on a trajectory given by \(\overrightarrow{{r}}=10 \alpha {t}^{2}\, \hat{{i}}+5 \beta({t}-5)\, \hat{{j}}\) Where \(\alpha\) and \(\beta\) are dimensional constants. The angular momentum of the particle becomes the same as it was for \({t}=0\) at time \({t}=\) .....\(seconds.\)JEE Mains 2021 Hard
- A small spherical droplet of density \(d\) is floating exactly half immersed in a liquid of density \(\rho\) and surface tension \(\mathrm{T}\). The radius of the droplet is (take note that the surface tension applies an upward force on the droplet)JEE Mains 2020 Hard
More PYQs from JEE Mains
- The figure given below shows an \(LCR\) series circuit with two switches \(S_1\) and \(S_2\). When switch \(S_1\) is closed keeping \(S_2\) open, the phase difference \((\phi)\) between the current and source voltage is \(30°\) and phase difference is \(60°\) when \(S_2\) is closed keeping \(S_1\) open. The value of \((3L_1 - L_2)\) is _______ H.
JEE Mains 2026 Hard - A triangular plate is shown. A force \(\overrightarrow{ F }=4 \hat{ i }-3 \hat{ j }\) is applied at point \(P\). The torque at point \(P\) with respect to point \('O'\) and \('Q'\) are
JEE Mains 2021 Hard - A parallel beam of monochromatic light of wavelength \(5000 \mathring A\) is incident normally on a single narrow slit of width \(0.001 \mathrm{~mm}\). The light is focused by convex lens on screen, placed on its focal plane. The first minima will be formed for the angle of diffraction of______________(degree).JEE Mains 2024 Hard