A battery of internal resistance $4\,\Omega $ is connected to the network of the resistance as shown in Fig. If the maximum power can be delivered to the network, the magnitude of $R$ in $\Omega $ should be

Two identical heater filaments are connected first in parallel and then in series. At the same applied voltage, the ratio of heat produced in same time for parallel to series will be:

A button battery is rated $3 \,V$ and $225 \,mAh . A$ cricket ball (mass $=0.163 \,kg$ ) having energy equal to that stored in the battety will have speed closest to ............ $\,m / s$

Two resistors having equal resistances are joined in series and a current is passed through the combination. Neglect any variation in resistance as the temperature changes. In a given time interval

A current of $3\,amp$ flows through the $2\,\Omega $ resistor shown in the circuit. The power dissipated in the $5\,\Omega $ resistor is ................. $watt$

A constant voltage is applied between the two ends of a metallic wire. If both the length and the radius of the wire are doubled, the rate of heat developed in the wire