The power rating of an electric motor which draws a current of $3.75\, A$ when operated at $200\, V$ is about:

Two wires have resistances of $2 \ \Omega$ and $4 \ \Omega$ and are connected to the same voltage. The ratio of heat dissipated in the resistances is:

An electric bulb is designed to draw power $P_0$ at voltage $V_0$. If the voltage is $V$,it draws a power $P$. Then:

$A$ resistor develops $300 \,J$ of thermal energy in $15 \,s$,when a current of $2 \,A$ is passed through it. If the current increases to $3 \,A$,the energy developed in $10 \,s$ is........$J.$

Which device can convert all electrical energy into heat?

Explain electrical energy and power.