For a thermocouple,the neutral temperature is $270\,^\circ C$ and the temperature of its cold junction is $20\,^\circ C$. If there is no deflection in the galvanometer,the temperature of the hot junction should be .............. $^\circ C$

If $E = at + bt^2$,what is the temperature of inversion?

Identify the correctness of the following statements:
$(1)$ The product of a volt and a coulomb is a joule.
$(2)$ The product of a volt and an ampere is a joule/second.
$(3)$ The product of a volt and a watt is a horsepower.
$(4)$ $A$ watt-hour can be measured in terms of an electron volt.

$A$ battery is charged at a potential of $15\, V$ for $8$ hours when the current flowing is $10\, A$. The battery on discharge supplies a current of $5\, A$ for $15$ hours. The mean terminal voltage during discharge is $14\, V$. The "Watt-hour" efficiency of the battery is .............. $\%$

Two bulbs rated $(25\, W - 220\, V)$ and $(100\, W - 220\, V)$ are connected in series to a $440\, V$ line. Which one is likely to fuse?

Three wires of copper,iron,and nickel are joined to form three junctions as shown in the figure. When the temperature of junction $1$ is kept at $50\,^{\circ}\text{C}$ with the other two junctions at $0\,^{\circ}\text{C}$,the sensitive galvanometer gives a deflection of $14$ divisions. When the temperature of junction $3$ is kept at $50\,^{\circ}\text{C}$,with the other two junctions at $0\,^{\circ}\text{C}$,the galvanometer gives a deflection of $11$ divisions. Then the deflection given by the galvanometer,when the temperature of junction $2$ is kept at $50\,^{\circ}\text{C}$,with the other two junctions at $0\,^{\circ}\text{C}$,will be (in $div$)