The work done to move a charge along an equipotential from \(A\) to \(B\):

1.	can not be defined as \(-\int_{A}^{B} { \vec E\cdot \vec{dl}}\)
2.	must be defined as \(-\int_{A}^{B} {\vec E\cdot \vec{dl}}\)
3.	is zero
4.	can have a non-zero value.

Choose the correct statement(s): 

In the circuit shown in the figure initially key \(K_1\) is closed and key \(K_2\) is open. Then \(K_1\) is opened and \(K_2\) is closed (order is important).
[Take \(Q_1\) and \(Q_2\) as charges on \(C_1\) and \(C_2\) and \(V_1\) and \(V_2\) as voltage respectively.]
       
Then,

A parallel plate capacitor is connected to a battery as shown in the figure. Consider two situations.

Equipotential at a great distance from a collection of charges whose total sum is not zero are approximately:

A parallel plate capacitor is made of two dielectric blocks in series. One of the blocks has thickness \(d_1\) and dielectric constant \(K_1\) and the other has thickness \(d_2\) and dielectric constant \(K_2\), as shown in the figure. This arrangement can be thought of as a dielectric slab of thickness \(d= d_1+d_2\) and effective dielectric constant \(K\). The \(K\) is:  

Three capacitors \(A\), \(B\) and \(C\) are connected in a circuit as shown in Fig. What is the charge in \(\mu \text{C}\) on the capacitor \(B\):