The charge on the $4\,\mu F$ capacitor in the given circuit is .... in $\mu C$.

Following operations can be performed on a capacitor: $X$ - connect the capacitor to a battery of $emf$ $E$. $Y$ - disconnect the battery. $Z$ - reconnect the battery with polarity reversed. $W$ - insert a dielectric slab of dielectric constant $K$ in the capacitor. Which of the following statements is correct?

While working on a physics project at a school physics lab,you require a $4 \,\mu F$ capacitor in a circuit across a potential difference of $1 \,kV$. Unfortunately,$4 \,\mu F$ capacitors are out of stock in your lab,but $2 \,\mu F$ capacitors which can withstand a potential difference of $400 \,V$ are available in plenty. If you decide to use the $2 \,\mu F$ capacitors in place of the $4 \,\mu F$ capacitor,what is the minimum number of capacitors required?

The potential differences that must be applied across the parallel and series combination of $3$ identical capacitors are such that the energy stored in them becomes the same. The ratio of the potential difference in the parallel combination to the series combination is:

Effective capacitance of parallel combination of two capacitors $C_{1}$ and $C_{2}$ is $10\; \mu F$. When these capacitors are individually connected to a voltage source of $1\; V,$ the energy stored in the capacitor $C_{2}$ is $4$ times that of $C_{1}$. If these capacitors are connected in series,their effective capacitance will be (in $; \mu F$)

In the circuit shown in the figure,four capacitors are connected to a battery. The potential difference across the $6 \ \mu F$ capacitor is......$V$.