A constant voltage is applied between the two ends of a uniform metallic wire. Some heat is developed in it. The heat developed doubles if:

1.	both the length and the radius of the wire are halved.
2.	both the length and the radius of the wire are doubled.
3.	the radius of the wire is doubled.
4.	The length of the wire is doubled.

 
Which of the above statements are correct?

Twelve wires of equal resistance \(R\) are connected to form a cube. The effective resistance between two diagonal ends \(A\) and \(E\) will be:

For the circuit shown in the figure, the current \(I\) will be:

Two solid conductors are made up of the same material and have the same length and the same resistance. One of them has a circular cross-section of area \(  𝐴 _1\) and the other one has a square cross-section of area \(A_2.\) The ratio of \(𝐴 _1 / 𝐴 _2  \) is:

For the circuit given below, Kirchhoff's loop rule for the loop \(BCDEB\) is given by the equation:

The equivalent resistance between \(A\) and \(B\) for the mesh shown in the figure is:

A charged particle having drift velocity of \(7.5\times10^{-4}~\text{ms}^{-1}\) in an electric field of \(3\times10^{-10}~\text{Vm}^{-1},\) has mobility of: 
1. \(2.5\times 10^{6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
2. \(2.5\times 10^{-6}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
3. \(2.25\times 10^{-15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)
4. \(2.25\times 10^{15}~\text{m}^2\text{V}^{-1}\text{s}^{-1}\)

A cell having an emf \(\varepsilon\) and internal resistance \(r\) is connected across a variable external resistance \(R\). As the resistance \(R\) is increased, the plot of potential difference \(V\) across \(R\) is given by:

1.		2.
3.		4.

In the circuit shown in the figure below, if the potential at point \(A\) is taken to be zero, the potential at point \(B\) will be:

1. \(+1\) V
2. \(-1\) V
3. \(+2\) V
4. \(-2\) V