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........... .

Heat produced in a wire of resistance $R$ due to current flowing at constant potential difference is proportional to

For ensuring dissipation of same energy in all three resistors $({R_1},\,{R_2},\,{R_3})$ connected as shown in figure, their values must be related as 

A rise of temperature of $4\,^oC$ is observed in a conductor by passing a current. If the current is tripled, the rise temperature will be .............. $^oC$

For driving a current of $2\, A$ for $6$ minutes in a circuit, $1000\, J$ of work is to be done. The $e.m.f.$ of the source in the circuit is ................ $V$

Forty electric bulbs are connected in series across a $220\, V$ supply. After one bulb is fused, the remaining $39$ are connected again in series across the same supply. The illumination will be