Electric Charges and Fields Physics - Electric Charges and Fields

1. 1cm $\Big(\sim\frac{1}{2}\times\text{diagonalof theone paisa coin}\Big)$,
2. 100m (~ length of a long building), and
3. 10⁶m (radius of the earth). Find the force on each such point charge in each of the three cases. What do you conclude from these results?

1. E in the outer region of the first plate is:

1. 17 × 10^-22 N/C
2. 1.5 × 10^-25 N/C
3. 1.9 × 10^-10 N/C
4. Zero.

2. E in the outer region of the second plate is:

1. 17 × 10^-22 N/C
2. 1.5 × 10^-15 N/C
3. 1.9 × 10^-10 N/C
4. Zero.

3. E between the plates is:

1. 17 × 10^-22 N/C
2. 1.5 × 10^-15 N/C
3. 1.9 × 10^-10 N/C
4. Zero.

4. The ratio of E from right side of B at distances 2cm and 4cm, respectively is:

1. 1 : 2
2. 2 : 1
3. 1 : 1
4. $1:\sqrt{2}$

5. ln order to estimate the electric field due to a thin finite plane metal plate, the Gaussian surface considered is:

1. Spherical.
2. Spherical.
3. Straight line.
4. None of these.

1. In coulomb's law, $\text{F}=\text{k}\frac{\text{q}_1\text{q}_2}{\text{r}^2}$ then on which of the following factors does the proportionality constant k depends?

1. Electrostatic force acting between the two charges.
2. Nature of the medium between the two charges.
3. Magnitude of the two charges.
4. Distance between the two charges.

2. Dimensional formula for the permittivity constant $\in_0$ of free space is:

1. [ML^-3 T⁴ A²]
2. [M^-1 L³ T² A²]
3. [M^-1 L^-3 T⁴ A²]
4. ML^-3 T⁴ A^-2]

3. The force of repulsion between two charges of 1C each, kept 1m apart in vaccum is:

1. $\frac{1}{9\times10^9}\text{N}$

2. 9 × 10⁹N
3. 9 × 10⁷N
4. $\frac{1}{9\times10^{12}}\text{N}$

4. Two identical charges repel each other with a force equal to 10 mgwt when they are 0.6m apart in air.(g = 10m s^-2). The value of each charge is:

1. 2mC
2. 2 × 10^-7mC
3. 2 nC
4. $2\mu\text{C}$

5. Coulomb's law for the force between electric charges most closely resembles with:

1. Law of conservation of energy.
2. Newton's law of gravitation.
3. Newton's 2^nd law of motion.
4. Law of conservation of charge.

1. Electric flux passing through surface S₆ is:

1. -24N m² C^-1
2. 24N m² C^-1
3. 32N m² C^-1
4. -32N m² C^-1

2. Electric flux passing through surface S₁ is:

1. -24N m² C^-1
2. 24N m² C^-1
3. 32N m² C^-1
4. -32N m² C^-1

3. The surfaces that have zero flux are:

1. S₁ and S₃
2. S₅ and S₆
3. S₂ and S₄
4. S₁ and S₂

4. The total net electric flux through all faces of the cube is:

1. 8N m² C^-1
2. -8N m² C^-1
3. 24N m² C^-1
4. Zero.

5. The dimensional formula of surface integral $\oint\vec{\text{E}}\cdot\text{d}\vec{\text{S}}$ of an electric field is:

1. [M L² T^-2 A^-1]
2. [M L³ T^-3 A^-1]
3. [M L^-1 T³ A^-3]
4. [M L^-3 T^-3 A^-1]

$\oint\limits_\text{S}\text{E.ds}=\frac{\text{q}}{\in_0}$