An expression for the rate of heat generated,if a current of $I$ ampere flows through a resistance of $R$ $\Omega$,is

Water in an electric kettle starts boiling in $15 \ min$ after being switched on. If the length of the heating wire is reduced to $2/3$ of its original length,the time taken to boil the same amount of water will be ........... $min$.

$A$ $220\, V$ and $800\, W$ electric kettle and three $220\, V$ and $100\, W$ bulbs are connected in parallel. On connecting this combination with a $220\, V$ electric supply,the total current will be ................ $A$.

Why is electric power transmitted at very high voltage over long distances to reduce Ohmic loss?

$A$ resistor develops $500 \, J$ of thermal energy in $20 \, s$ when a current of $1.5 \, A$ is passed through it. If the current is increased from $1.5 \, A$ to $3 \, A$,what will be the energy (in $J$) developed in $20 \, s$?

The emf of a storage battery of a car is $6.0 \ V$. If the internal resistance of the battery is $0.2 \ \Omega$, then the maximum power drawn from the battery is . . . . . . $W$.