A galvanometer having a coil resistance of $30\,\Omega $ shows full scale deflection when a current of $2\,A$ passes through it. It can be converted into an ammeter to read currents upto $10\,A$ by
Medium
Download our app for free and get started
$S = \frac{{{I_g}{R_g}}}{{I - {I_g}}} = \frac{{(2)(30)}}{{10 - 2}} = \frac{{2 \times 30}}{8} = \frac{{15}}{2} = 7.5\,\Omega $
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
- 1A steady current $I$ flows along an infinitely long hollow cylindrical conductor of radius $R$. This cylinder is placed coaxially inside an infinite solenoid of radius $2 \ R$. The solenoid has $n$ turns per unit length and carries a steady current $I$. Consider a point $P$ at a distance $r$ from the common axis. The correct statement$(s)$ is (are) :View Solution
$(A)$ In the region $0 < r < R$, the magnetic field is non-zero.
$(B)$ In the region $R < r < 2 R$, the magnetic field is along the common axis.
$(C)$ In the region $R < r < 2 R$, the magnetic field is tangential to the circle of radius $r$, centered on the axis.
$(D)$ In the region $r > 2 R$, the magnetic field is non-zero.
- 2Due to the flow of current in a circular loop of radius $R$, the magnetic field produced at the centre of the loop is $B$. The manetic moment of the loop isView Solution
- 3View SolutionA current carrying coil is subjected to a uniform magnetic field. The coil will orient so that its plane becomes
- 4Find out magnetic field at point $O$ ?View Solution
- 5A small square loop of wire of side $l$ is placed inside a large square loop of wire of side $L(L >> l)$. The loops are coplaner and their centres coincide. The mutual inductance of the system is propotional toView Solution
- 6View SolutionMark out the correct options.
- 7View SolutionIf an electron and a proton having same momenta enter perpendicular to a magnetic field, then
- 8A proton of energy $8\, eV$ is moving in a circular path in a uniform magnetic field. The energy of an alpha particle moving in the same magnetic field and along the same path will be.....$eV$View Solution
- 9The electric current in a circular coil of four turns produces a magnetic induction $32\,T$ at its centre. The coil is unwound and is rewound into a circular coil of single turn, the magnetic induction at the centre of the coil by the same current will be $..........\,T$View Solution
- 10An infinitely long conductor $PQR$ is bent to from a right angle as shown. A current $I$ flows through $PQR$ . The magnetic field due to this current at the point $M$ is $H_1$ . Now, another infinitely long straight conductor $QS$ is connected at $Q$ so that the current in $PQ$ remaining unchanged. The magnetic field at $M$ is now $H_2$ . The ratio $H_1/H_2$ is given byView Solution
