A dipole (\(p\)) is placed so that it is always aligned along the x-axis but it can undergo displacement along the x-axis. The dipole is placed exactly midway between two fixed charges \(-Q\) and \(Q,\) in two possible ways.
                            
Then, the dipole is:

1.	stable in both A, B
2.	stable in A, unstable in B
3.	unstable in A, stable in B
4.	unstable in both A, B

A dielectric slab is inserted between the plates of an isolated charged capacitor. Which of the following quantities will remain the same?

Choose the correct option:
1. (a), (b)
2. (b) only
3. (c), (a)
4. (a), (d)

A thin, metallic spherical shell contains a charge \(\mathrm{Q}\) on it. A point charge \(\mathrm{q}\) is placed at the centre of the shell and another charge \(\mathrm{q}_1\) is placed outside as it is shown in the figure. All the three charges are positive. The force on the charge at the centre is:
         
1. towards left
2. towards right
3. upward
4. zero

The electric field at the origin is along the positive x-axis. A small circle is drawn with the centre at the origin cutting the axes at points \(\mathrm A\), \(\mathrm B\), \(\mathrm C\) and \(\mathrm D\) having coordinates \((a,0),(0,a),(-a,0),(0,-a)\) respectively. Out of the points on the periphery of the circle, the potential is minimum at:
1. \(\mathrm A\)
2. \(\mathrm B\)
3. \(\mathrm C\)
4. \(\mathrm D\)

When the separation between two charges is increased, the electric potential energy of the charges: