$A$ current $i$ passes through a wire of length $l$, radius of cross-section $r$ and resistivity $\rho$. The rate of heat generation is

Which of the following statements is correct?

An electric room radiator which operates at $225\, V$ has a resistance of $50\, \Omega$. The power of the radiator is approximately ............... $W$.

Consider an electrical conductor connected across a potential difference $V$. Let $\Delta q$ be a small charge moving through it in time $\Delta t$. If $I$ is the electric current through it,
$I$. the kinetic energy of the charge increases by $I V \Delta t$.
$II$. the electric potential energy of the charge decreases by $I V \Delta t$.
$III$. the thermal energy of the conductor increases by $I V \Delta t$.
Choose the correct option.

In India,electricity is supplied for domestic use at $220\,V$. It is supplied at $110\,V$ in the $USA$. If the resistance of a $60\,W$ bulb for use in India is $R$,then the resistance of a $60\,W$ bulb for use in the $USA$ will be:

You are given three bulbs of $25\, W$,$40\, W$,and $60\, W$. Which of them has the lowest resistance?