The charge on \(500~\text{cc}\) of water due to protons will be: 

1. \(6.0\times 10^{27}~\text{C}\) 2. \(2.67\times 10^{7}~\text{C}\)
3. \(6\times 10^{23}~\text{C}\) 4. \(1.67\times 10^{23}~\text{C}\)
Subtopic:  Electric Charge |
 59%
Level 3: 35%-60%
Hints
Links

A polythene piece rubbed with wool is found to have a negative charge of \(3 \times10^{-7}~\text{C}.\) Transfer of mass from wool to polythene is:
1. \(0.7\times10^{-18}~\text{kg}\)
2. \(1.7\times10^{-17}~\text{kg}\)
3. \(0.7\times10^{-17}~\text{kg}\)
4. \(1.7\times10^{-18}~\text{kg}\)

Subtopic:  Electric Charge |
 62%
Level 2: 60%+
Hints
Links

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. \(Q_1=\frac{Q}{2}, Q_2=\frac{Q}{2}\)            

Subtopic:  Coulomb's Law |
 85%
Level 1: 80%+
Hints

advertisementadvertisement

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
Subtopic:  Coulomb's Law |
 78%
Level 2: 60%+
PMT - 1979
Hints
Links

Two charges \(2~\mu\text{C}\) and \(8~\mu\text{C}\) are separated by \(6~\text{cm}.\) The neutral point is at:
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 \(8~\mu\text{C}.\)
Subtopic:  Coulomb's Law |
 79%
Level 2: 60%+
Hints
Links

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. \( 10^{25} ~\text{m/s}^2\)
Subtopic:  Coulomb's Law |
 76%
Level 2: 60%+
NEET - 2020
Hints
Links

advertisementadvertisement

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 \(AB\)

Subtopic:  Coulomb's Law |
 69%
Level 2: 60%+
Hints
Links

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

Subtopic:  Coulomb's Law |
 68%
Level 2: 60%+
PMT - 2003
Hints
Links

Three charges are placed at the vertices of an equilateral triangle of side \(a\) as shown in the following figure. The force experienced by the charge placed at the vertex \(A\) in a direction normal to \(BC\) is: 

1. \(Q^{2} / \left(\right. 4 \pi \epsilon_{0} a^{2} \left.\right)\)

2. \(- Q^{2} / \left(\right. 4 \pi \epsilon_{0} a^{2} \left.\right)\)

3. zero

4. \(Q^{2} / \left(\right. 2 \pi \epsilon_{0} a^{2} \left.\right)\)

Subtopic:  Coulomb's Law |
 64%
Level 2: 60%+
AIIMS - 2003
Hints
Links

advertisementadvertisement

Two small spheres each having the charge \(+Q\) are suspended by insulating threads of length \(L\) from a hook. If this arrangement is taken in space where there is no gravitational effect, then the angle between the two suspensions and the tension in each will be:

1. \(180^\circ,\) \(\frac{1}{4 \pi \epsilon_{0}} \frac{Q^{2}}{(2 L )^{2}}\)

2. \(90^\circ,\) \(\frac{1}{4 \pi \epsilon_{0}} \frac{Q^{2}}{(L )^{2}}\)

3. \(180^\circ,\) \(\frac{1}{4 \pi \epsilon_{0}} \frac{Q^{2}}{2 L ^{2}}\)

4. \(180^\circ,\) \(\frac{1}{4 \pi \epsilon_{0}} \frac{Q^{2}}{ L ^{2}}\) 

Subtopic:  Coulomb's Law |
 69%
Level 2: 60%+
Hints
Links