Above neutral temperature,thermo $e.m.f.$ in a thermocouple

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?

In a silver voltameter, $2.89 \ g$ of silver is deposited in $10 \ minutes$. The heat produced in a $20 \ \Omega$ resistor for the same time will be ................ $kJ$.

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.

The charge flowing through a resistance $R$ varies with time according to $Q = at - bt^2$. The total heat produced in $R$ is: (assume that the direction of current is not reversed)

Suppose the drift velocity $v_d$ in a material varies with the applied electric field $E$ as $v_d \propto \sqrt{E}$. Then the $V-I$ graph for a wire made of such a material is best given by: