In the circuit shown here,the readings of the ammeter and voltmeter are

The thermoelectric electromotive force $e$ is given by $e = \alpha t - \frac{1}{2}\beta t^2$. If the temperature of the cold junction is $0 \, ^\circ C$,find the temperature of inversion $t_i$. (Given: $\alpha = 500.0 \, \mu V/^\circ C$,$\beta = 5.0 \, \mu V/^\circ C^2$)

There are two electric bulbs of $40\, W$ and $100\, W$. Which one will be brighter when first connected in series and then in parallel?

For the circuit shown in the figure:
$(A)$ The current $I$ through the battery is $7.5 \text{ mA}$.
$(B)$ The potential difference across $R_L$ is $18 \text{ V}$.
$(C)$ The ratio of powers dissipated in $R_1$ and $R_2$ is $3$.
$(D)$ If $R_1$ and $R_2$ are interchanged,the magnitude of the power dissipated in $R_L$ will decrease by a factor of $9$.

The variation of current flowing through an electric heater with time,when it is switched on,is shown in the figure. Considering the change in resistance with temperature,which of the following graphs is correct?

$A$ battery is charged by a $15\,V$ battery for $8\,h$ at a current of $10\,A$. When this battery discharges, it provides a current of $5\,A$ for $15\,h$. The average terminal voltage during discharge is $14\,V$. What is the $watt-hour$ efficiency of this battery in $\%$?