The figure shows a tetrahedron,each side of which has a resistance $r$. Choose the correct diagram$(s)$,which show a two-dimensional equivalent of the tetrahedron.

Two electric bulbs marked $25\ W - 220\ V$ and $100\ W - 220\ V$ are connected in series to a $440\ V$ supply. Which of the bulbs will fuse?

For gold plating on a copper chain,the substance required in the form of solution is

Two electrical bulbs marked $40\, W, 220\, V$ and $60\, W, 220\, V$ are connected in series across a $220\, V$ supply. The effective power is $P_1$. When they are connected in parallel across the same supply, the effective power is $P_2$. The ratio $(P_1/P_2)$ is:

The cold junction of a thermocouple is at $0^{\circ} C$. The thermo e.m.f. produced in the thermocouple is given by the equation $E = 16T - 0.04T^2$, where $T$ is the temperature of the hot junction. The temperature of inversion and the neutral temperature of the thermocouple are:

The rate of increase of thermo-e.m.f. with temperature at the neutral temperature of a thermocouple [$AIPMT$ $2011$]