A capacitor $C$ is charged to a potential difference $V$ and battery is disconnected. Now if the capacitor plates are brought close slowly by some distance :
some $+ve$ work is done by external agent
energy of capacitor will decrease
energy of capacitor will increase
none of the above
The energy stored in a condenser of capacity $C$ which has been raised to a potential $V$ is given by
A $400\, pF$ capacitor is charged with a $100\, V$ battery. After disconnecting battery this capacitor is connected with another $400\, pF$ capacitor. Then find out energy loss.
Two capacitors of equal capacitance $(C_1 = C_2)$ are shown in the figure. Initially, while the switch $S$ is open, one of the capacitors is uncharged and the other carries charge $Q_0$. The energy stored in the charged capacitor is $U_0$. Sometimes after the switch is closed, the capacitors $C_1$ and $C_2$ carry charges $Q_1$ and $Q_2$, respectively; the voltages across the capacitors are $ V_1$ and $V_2$; and the energies stored in the capacitors are $U_1$ and $U_2$. Which of the following statements is INCORRECT ?
In a uniform electric field, a cube of side $1\ cm$ is placed. The total energy stored in the cube is $8.85\ μJ$ . The electric field is parallel to four of the faces of the cube. The electric flux through any one of the remaining two faces is
A $40$ $\mu F$ capacitor in a defibrillator is charged to $3000\,V$. The energy stored in the capacitor is sent through the patient during a pulse of duration $2\,ms$. The power delivered to the patient is......$kW$