A uniform heating wire of resistance $36\, \Omega$ is connected across a potential difference of $240\, {V}$ The wire is then cut into half and potential difference of $240\, {V}$ is applied across each half separately. The ratio of power dissipation in first case to the total power dissipation in the second case would be $1: {x}$, where ${x}$ is........... .
A$4$
B$40$
C$0.4$
D$400$
JEE MAIN 2021, Medium
Download our app for free and get started
A$4$
a First case ${P}_{1}=\frac{{V}^{2}}{{R}}=\frac{(240)^{2}}{36}$
Second case Resistance of each half $=18 \,\Omega$
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.*
For the circuit shown, with ${R_1} = 1.0\,\Omega $, ${R_2} = 2.0\,\Omega $, ${E_1} = 2\,V$ and ${E_2} = {E_3} = 4\,V$, the potential difference between the points $‘a’$ and $‘b’$ is approximately (in $V$)
In the following circuit, $5$ $\Omega$ resistor develops $45$ $J/s$ due to current flowing through it. The power developed per second across $12$ $\Omega$ resistor is ............. $W$
A resistance of $4\,\Omega $ and a wire of length $5\,m$ and resistance $5\,\Omega $ are joined in series and connected to a cell of $e.m.f.$ $10\, V$ and internal resistance $1\,\Omega $. A parallel combination of two identical cells is balanced across $300\, cm$ of the wire. The $e.m.f.$ $E$ of each cell is ........... $V$
Two coils require $20$ minutes and $60$ minutes respectively to produce same amount of heat energy when connected separately to the same source. If they are connected in parallel arrangement to the same source; the time required to produce same amount of heat by the combination of coils, will be________ $min$
The value of the resistance $R$ in figure is adjusted such that power dissipated in the $2\,\Omega $ resistor is maximum. Then the power dissipated in the $2\,\Omega $ will be ................ $W$