Question
One conducting $U$ tube can slide inside another as shown in figure, maintaining electrical contacts between the tubes. The magnetic field $B$ is perpendicular to the plane of the figure. If each tube moves towards the other at a constant sped $v$ then the emf induced in the circuit in terms of $B,\,l$ and $v$ where $l$ is the width of each tube, will be

Answer

Two emf's induces in the closed circuit each of value $Bl\,v$. These two emf's are additive. So ${E_{{\rm{net}}}} = 2Bl\,v$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

The diagram to the right shows the lowest four energy levels for an electron in $a$ hypothetical atom. The electron is excited to the $-1\, eV$ level of the atom and transitions to the lowest energy state by emitting only two photons. Which of the following energies could not belong to either of the photons? ......... $eV$
An electron is moving in a circular orbit of radius $R$ with an angular acceleration $\alpha$ . At the centre of the orbit is kept a conducting loop of radius $r, (r < < R).$ The $e.m.f$ induced in the smaller loop due to the motion of the electron is
As shown in the figure, a particle of mass $10$ $kg$ is placed at a point $A$. When the particle is slightly displaced to its right, it starts moving and reaches the point $B$. The speed of the particle at $B$ is $x\, m / s$. (Take $\left. g =10\, m / s ^{2}\right)$ The value of $'x'$ to the nearest integer is.........
If a particle moves in a circle describing equal angles in equal times, its velocity vector
In a series $LCR$ current the voltage across resistance, capacitance and inductance is $10\, V$ each. If the inductor is short circuited, the voltage across the capacitor will be:-
Two block of masses $m_1$ and $m_2$ connected with the help of a spring of spring constant $k$ initially to natural length as shown. A sharp impulse is given to mass $m_2$ so that it acquires a velocity $v_0$ towards right. If the system is kept an smooth floor then find the maximum elongation that the spring will suffer
What is ratio of surface energy of $1$ small drop and $1$ large drop, if $1000$ small drops combined to form $1$ large drop
A wire of resistance $20 \Omega$ is divided into $10$ equal parts. A combination of two parts are connected in parallel and so on. Now resulting pairs of parallel combination are connected in series. The equivalent resistance of final combination is_______.0$\Omega$.
For a substance the average life for $\alpha$-emission is $1620$ years and for $\beta$ emission is $405$ years. After how much time the $1/4$ of the material remains after $\alpha$ and $\beta$ emission .......$years$
Four open organ pipes of different lengths and different gases at same temperature as shown in figure. Let $f_A$, $f_B$, $f_C$ and $f_D$ be their fundamental frequencies then :[Take ${\gamma _{c{o_2}}} = 7/5$]