The $V-I$ graph for a conductor at temperatures $T_1$ and $T_2$ is as shown in the figure. Then $(T_2 - T_1)$ is proportional to

What is the total number of orbitals associated with the principal quantum number $n=3$?

For a transistor,the current amplification factor $\alpha$ is $0.8$. The transistor is connected in a common emitter configuration. The change in the collector current when the base current changes by $6 \, mA$ is ..... $mA$.

$A$ galvanometer may be converted into an ammeter or a voltmeter. In which of the following cases will the resistance of the device so obtained be the largest?

$A$ vessel contains $110\,g$ of water. The heat capacity of the vessel is equivalent to $10\,g$ of water. The initial temperature of the water in the vessel is $10\,^{\circ}C$. If $220\,g$ of hot water at $70\,^{\circ}C$ is poured into the vessel,the final temperature,neglecting radiation loss,will be ........ $^{\circ}C$.

If the sum of the roots of the equation $x^2 + px + q = 0$ is three times their difference,then which of the following is true?