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.*
The variation of applied potential and current flowing through a given wire is shown in figure. The length of wire is $31.4 \,cm$. The diameter of wire is measured as $2.4 \,cm$. The resistivity of the given wire is measured as $x \times 10^{-3} \,\Omega cm$. The value of $x$ is_______ [Take $\pi=3.14]$
A battery of $e.m.f.$ $10\, V$ and internal resistance $0.5\, ohm$ is connected across a variable resistance $R$. The value of $R$ for which the power delivered in it is maximum is given by ......... $ohm$
In the given circuit, an ideal voltmeter connected across the $10\,\Omega $ resistance reads $2\, V$. The internal resistance $r$, of each cell is ................... $\Omega$
In the circuit shown below (on the left) the resistance and the emf source are both variable. The graph of seven readings of the voltmeter and the ammeter ( $V$ and $I$, respectively) for different settings of resistance and the emf, taken at equal intervals of time $\Delta t$, are shown below (on the right) by the dots connected by the curve $E F G H$. Consider the internal resistance of the battery to be negligible and the voltmeter an ammeter to be ideal devices. (Take, $R_0 \equiv \frac{V_0}{I_0}$ ).
Then, the plot of the resistance as a function of time corresponding to the curve $E F G H$ is given by
Model a torch battery of length $l$ to be made up of a thin cylindrical bar of radius $'a'$ and a concentric thin cylindrical shell of radius ' $b$ ' fille in between with an electrolyte of resistivity $\rho$ (see figure). If the battery is connected to a resistance of value $R ,$ the maximum Joule heating in $R$ will take place for
A student uses the resistance of a known resistor $(1 \,\Omega)$ to calibrate a voltmeter and an ammeter using the circuits shown below. The student measures the ratio of the voltage to current to be $1 \times 10^3 \,\Omega$ in circuit $(a)$ and $0.999 \,\Omega$ in circuit $(b)$. From these measurements, the resistance (in $\Omega$ ) of the voltmeter and ammeter are found to be close to