Q. No.A total charge \(Q\) is broken in two parts \(Q_1\) and \(Q_2\) and they are placed at a distance \(R\) from each other. The maximum force of repulsion between them will occur, when:
| 1. | \(Q_2=\frac{Q}{R}, Q_1=Q-\frac{Q}{R}\) |
| 2. | \(Q_2=\frac{Q}{4}, Q_1=Q-\frac{2 Q}{3}\) |
| 3. | \(Q_2=\frac{Q}{4}, Q_1=\frac{3 Q}{4}\) |
| 4. | \(Q_1=\frac{Q}{2}, Q_2=\frac{Q}{2}\) |
Two charges \(+2\) C and \(+6\) C are repelling each other with a force of \(12\) N. If each charge is given \(-2\) C of charge, then the value of the force will be:
| 1. | \(4\) N (attractive) | 2. | \(4\) N (repulsive) |
| 3. | \(8\) N (repulsive) | 4. | zero |
| 1. | \(4~\text{cm}\) from \(2~\mu\text{C}.\) |
| 2. | \(2~\text{cm}\) from \(2~\mu\text{C}.\) |
| 3. | \(2~\text{cm}\) from \(8~\mu\text{C}.\) |
| 4. | \(3~\text{cm}\) from \(8~\mu\text{C}.\) |
Two positive ions, each carrying a charge \(q\), are separated by a distance \(d\). If \(F\) is the force of repulsion between the ions, the number of electrons missing from each ion will be:
(\(e\) is the charge on an electron)
| 1. | \(\frac{4 \pi \varepsilon_{0} F d^{2}}{e^{2}}\) | 2. | \(\sqrt{\frac{4 \pi \varepsilon_{0} F e^{2}}{d^{2}}}\) |
| 3. | \(\sqrt{\frac{4 \pi \varepsilon_{0} F d^{2}}{e^{2}}}\) | 4. | \(\frac{4 \pi \varepsilon_{0} F d^{2}}{q^{2}}\) |
The acceleration of an electron due to the mutual attraction between the electron and a proton when they are \(1.6~\mathring{A}\) apart is:
\(\left(\frac{1}{4 \pi \varepsilon_0}=9 \times 10^9~ \text{Nm}^2 \text{C}^{-2}\right)\)
| 1. | \( 10^{24} ~\text{m/s}^2\) | 2 | \( 10^{23} ~\text{m/s}^2\) |
| 3. | \( 10^{22}~\text{m/s}^2\) | 4. | \( 10^{25} ~\text{m/s}^2\) |
| 1. | \(\frac{4F}{3}\) | 2. | \(F\) |
| 3. | \(\frac{9F}{16}\) | 4. | \(\frac{16F}{9}\) |
| 1. | Newton metre2 / Coulomb2 |
| 2. | Coulomb2 /Newton metre2 |
| 3. | Coulomb2/ (Newton metre)2 |
| 4. | Coulomb/Newton metre |
Four charges are arranged at the corners of a square \(ABCD\) as shown in the figure. The force on a positive charge kept at the center of the square is:
| 1. | zero |
| 2. | along diagonal \(AC\) |
| 3. | along diagonal \(BD\) |
| 4. | perpendicular to the side \(AB\) |
| 1. | \(7.20\) N | 2. | \(11.25~\text{N}\) |
| 3. | \(22.50\) N | 4. | \(45.00\) N |
Five balls numbered \(1\) to \(5\) are suspended using separate threads. Pairs \((1, 2), (2, 4),\) and \((4, 1)\) show electrostatic attraction, while pairs \((2, 3)\) and \((4, 5)\) show repulsion. Therefore ball \((1)\) must be:
1. positively charged
2. negatively charged
3. neutral
4. made of metal
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