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An oil drop of mass $m = 2.4 \cdot 10^{-15}$ kg is in equilibrium between the horizontal plates of a parallel-plate capacitor. The distance between the plates is $d = 1$ cm, the voltage is $U = 500$ V, and the upper plate is positively charged (see the figure). Find the charge of the drop,…
Two capacitors of capacitances $C_1 = 2$ µF and $C_2 = 3$ µF are connected in series to a voltage source $U = 100$ V (see the circuit). Find the capacitance of the combination, the charge on each capacitor and the voltage across each of them. The capacitors were uncharged before the connection.
Positive point charges $q_1 = 12$ nC and $q_2 = 16$ nC are placed at vertices $A$ and $B$ of a right triangle $ABC$ with the right angle at $C$ and equal legs $CA = CB = a = 6$ cm. A positive point charge $q_0 = 1$ nC is placed at vertex $C$ (see the figure). Find the magnitude of the force acting…
A ball of mass $m = 2$ g hanging on a light silk thread is placed in a horizontal uniform electric field of strength $E = 10$ kV/m. The ball is deflected and the thread makes an angle $\alpha = 45°$ with the vertical (see the figure). Find the charge of the ball (magnitude and sign) and the tension…
A capacitor of capacitance $C = 2$ uF is charged to a voltage $U = 100$ V. Find the energy stored in the capacitor.
Two point charges of the same sign, $q = 4$ uC each, repel each other with a force $F = 9$ N. Find the distance between the charges. Coulomb's constant is $k = 9 \cdot 10^9$ N·m²/C².
Two point charges $q_1 = 2$ uC and $q_2 = 3$ uC are placed $r = 0.1$ m apart. Find the electrostatic force between the charges. Coulomb's constant is $k = 9 \cdot 10^9$ N·m²/C².