In an experiment of meter bridge, a null point is obtained at the centre of the bridge wire. When a resistance of $10\, ohm$ is connected in one gap, the value of resistance in other gap is ............. $\Omega$
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.*
A wire is broken in four equal parts. A packet is formed by keeping the four wires together. The resistance of the packet in comparison to the resistance of the wire will be
The thermo $e.m.f.$ of a thermo-couple is $25\,\mu V{/^o}C$ at room temperature. A galvanometer of $40\, ohm$ resistance, capable of detecting current as low as ${10^{ - 5}}\,A,$ is connected with the thermocouple. The smallest temperature difference that can be detected by this system is ................ $^oC$
A potential divider is used to give outputs of $4\,V$ and $8\,V$ from a $12\,V$ source. Which combination of resistances, $(R_1 : R_2 : R_3)$ gives the correct voltages
In given hollow cylindrical conductor current density is $J = \frac{J_0}{r^2}$ where $J_0$ is constant and $r$ is the distance from axis of cylinder. If radius of inner surface is $'a'$ and radius of outer surface is $2a$ then find current passed through the conductor.
A $100\, W \, bulb\, B_1$ and two $60\, W \,bulbs \,B_2$ and $B_3$, are connected to a $220\, V$ source, as shown in Figure. Now $P_1, P_2$ and $P_3$ are the output powers of the bulbs $B_1, B_2$ and $B_3$ respectively. Then
Drift speed of electrons, when $1.5\, A$ of current flows in a copper wire of cross section $5\, mm^2$, is $v$. If the electron density in copper is $9 \times 10^{28}\, m^3$ the value of $v$ in $mm/s$ is close to (Take charge of electron to be $= 1.6 \times 10^{-19}\, C$)
$10$ resistors, each of resistance $R$ are connected in series to a battery of $emf$ $E$ and negligible internal resistance. Then those are connected in parallel to the same battery, the current is increased $n$ times. The value of $n$ is :