A cell of $e.m.f.$ $1.5\,V$ having a finite internal resistance is connected to a load resistance of $2\,\Omega $. For maximum power transfer the internal resistance of the cell should be ............. $ohm$
Easy
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
- 1The circuit shown here is used to compare the emf of two cells $E_1$ and $E_2 (E_1 > E_2)$. The null point is at $C$ when the galvanometer is connected to $E_1$. When the galvanometer is connected to $E_2$, the null point will beView Solution
- 2In the box shown current $i$ enters at $H$ and leaves at $C$. If $i_{AB} = \frac{{\text{i}}}{6}$ , $i_{DC} = \frac{{\text{2i}}}{3}$ ,$i_{HA} = \frac{{\text{i}}}{2} , i_{GF} = \frac{{\text{i}}}{6} , i_{HE} = \frac{{\text{i}}}{6}$ , choose the branch in which current is zeroView Solution
- 3The resistance of the filament of a lamp increases with the increase in temperature. A lamp rated $100\, W, 220\, V$ is connected across $220\, V$ power supply. If the voltage drops by $10\%$ then the power of lamp will beView Solution
- 4An electric toaster has resistance of $60\ \Omega$ at room temperature $\left(27^{\circ} \mathrm{C}\right)$. The toaster is connected to a $220 \mathrm{~V}$ supply. If the current flowing through it reaches $2.75 \mathrm{~A}$, the temperature attained by toaster is around : (if $\alpha=2 \times 10^{-4} /{ }^{\circ} \mathrm{C}$ )View Solution
- 5The electric field $E$, current density $J$ and conductivity $\sigma$ of a conductor are related asView Solution
- 6Four wires of the same diameter are connected in turn between two points, maintained at a constant potential difference. Their resistivities are; $\rho $ and $L$ (wire $1$ )., $1.2\,\rho $ and $1.2\,L$ (wire $2$ ), $0.9\,\rho $ and $0.9\,L$ (wire $3$ ) and $\rho $ and $1.5\,L$ (wire $4$ ). Rank the wires according to the rates at which energy is dissipated as heat, greatest firstView Solution
- 7Three copper rods are subjected to different potential difference. Compare the drift speed of electrons through them. Assume that all $3$ are at the same temperature.View Solution
Length Diameter Potential difference $(A)$ $L$ $3d$ $V$ $(B)$ $2L$ $d$ $2V$ $(C)$ $3L$ $2d$ $2V$ - 8View SolutionThe equivalent resistance of the infinite network given below is :
- 9Consider a metallic cube of edge length $L$. Its resistance, $R$, measured across its opposite faces is $R =\frac{ m _{ e } v }{ ne ^2 L ^2}$, where $n$ is the number density and $v$ is the drift speed of electrons in the cube, and $e$ and $m _{ e }$ are the charge and mass of an electron respectively. Assuming the de-Broglie wavelength of the electron to be $L$, the maximum resistance of the sample is closest to ............. $\,\Omega$ $\left(e=1.60 \times 10^{-19} \,C ; m _{ e }=9.11 \times 10^{-31} \,kg\right.$; Planck's constant, $h=6.63 \times 10^{-34} \,Js$ )View Solution
- 10The internal resistance of a $2.1\, V$ cell which gives a current of $0.2\, A$ through a resistance of $10\,\Omega$ is ............. $\Omega$View Solution