A small coil of $N$ $turns$ has an effective area $A$ and carries a current $I$. It is suspended in a horizontal magnetic field $\overrightarrow B $ such that its plane is perpendicular to $\overrightarrow B $. The work done in rotating it by $180^\circ $ about the vertical axis is
Medium
Download our appand get started for free
Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*
Similar Questions
- 1An $\alpha$ particle is moving along a circle of radius $R$ with a constant angular velocity $\omega $. Point $A$ lies in the same plane at a distance $2R$ from the centre. Point $A$ records magnetic field produced by $\alpha$ particle. If the minimum time interval between two successive times at which $A$ records zero magnetic field is $‘t’,$ find the angular speed $\omega $, in terms of $t.$View Solution
- 2A current of $1\,A$ is flowing on the sides of an equilateral triangle of side $4.5\times10^{-2}\,m$ . The magnetic field at the centre of the triangle will beView Solution
- 3A current of $10\, ampere$ is flowing in a wire of length $1.5\, m$. A force of $15\, N$ acts on it when it is placed in a uniform magnetic field of $2$ $tesla$. The angle between the magnetic field and the direction of the current is.....$^o$View Solution
- 4Consider three quantities $x = E/B,$ $y =\sqrt {1/{\mu _0}{\varepsilon _0}} $ and $z = l$ . Here, $l$ is the length of a wire, $C$ is a $CR$ capacitance and $R$ is a resistance. All other symbols have standard meanings.View Solution
- 5A long copper tube of inner radius $R$ carries a current $i$. The magnetic field $B$ inside the tube isView Solution
- 6The ammeter has range $1\, ampere$ without shunt. the range can be varied by using different shunt resistances. The graph between shunt resistance and range will have the natureView Solution
- 7The current sensitivity of a galvanometer can be increased by:View Solution
$(A)$ decreasing the number of turns
$(B)$ increasing the magnetic field
$(C)$ decreasing the area of the coil
$(D)$ decreasing the torsional constant of the spring
Choose the most appropriate answer from the options given below.
- 8Two concentric coils each of radius equal to $2\pi \,{\rm{ }}cm$ are placed at right angles to each other. $3$ $ampere$ and $4$ $ampere$ are the currents flowing in each coil respectively. The magnetic induction in $Weber/{m^2}$ at the centre of the coils will be $({\mu _0} = 4\pi \times {10^{ - 7}}\,Wb/A.m)$View Solution
- 9A galvanometer gives full scale reading of $50\ mA$ , when a $p.d.$ , across its terminals is $0.15\ V$ . It can be used as an ammeter of range $0 - 100\ A$ by connecting a shunt resistance ofView Solution
- 10An electron having a charge e moves with a velocity $v$ in positive $x$ direction. A magnetic field acts on it in positive $y$ direction. The force on the electron acts in (where outward direction is taken as positive $z$-axis).View Solution