In the circuit diagram shown, each battery is ideal having an e.m.f. of $1\  volt$. Each resistor has a resistance of $1\Omega $ Ammotor$(A)$ has a resistance of $1\Omega $ Find the reading of the ammeter and the total thermal power produced in the circuit 

Which device can convert all electrical energy into heat

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 ............ $\,m / s$

Four bulbs $B_1 , B_2, B_3$ and $B_4$ of $100\, W$ each are connected to $220\, V$ main as shown in the figure. The reading in an ideal ammeter will be ............... $A$

A resistor ${R_1}$ dissipates the power $P$ when connected to a certain generator. If the resistor ${R_2}$ is put in series with ${R_1}$, the power dissipated by ${R_1}$

Model a torch battery of length $l$ to be made up of a thin cylindrical bar of radius $'a'$ and a concentric thin cylindrical shell of radius ' $b$ ' fille in between with an electrolyte of resistivity $\rho$ (see figure). If the battery is connected to a resistance of value $R ,$ the maximum Joule heating in $R$ will take place for