When \(10^{19}\) electrons are removed from a neutral metal plate, the electric charge on it is? 

1.	\(-1.6\) C	2.	\(+1.6\) C
3.	\(10^{19}\) C	4.	\(10^{-19}\) C

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.

Two spherical conductors B and C having equal radii and carrying equal charges in them repel each other with a force F when kept apart at some distance. A third spherical conductor having same radius as that of B but uncharged is brought in contact with B, then brought in contact with C and finally removed away from both. The new force of repulsion between B and C is:

1. F/4

2. 3 F/4

3. F/8

4. 3 F/8

An infinite number of charges, each of charge 1 μC, are placed on the x-axis with co-ordinates x = 1, 2, 4, 8, ....∞. If a charge of 1 C is kept at the origin, then what is the net force acting on 1 C charge?

Three identical positive point charges, as shown are placed at the vertices of an isosceles right-angled triangle. Which of the numbered vectors coincides in direction with the electric field at the mid-point M of the hypotenuse?
                
1. 1
2. 2
3. 3
4. 4

An electron enters an electric field with its velocity in the direction of the electric lines of force. Then: 

A charged ball B hangs from a silk thread S, which makes an angle θ with a large charged conducting sheet P, as shown in the figure. The surface charge density σ of the sheet is proportional to: 

1. sin θ

2. tan θ

3. cos θ

4. cot θ

Two equal negative charges of charge – q are fixed at the points (0, a) and (0, –a) on the Y-axis. A positive charge Q is released from rest at the point (2a, 0) on the X-axis. The charge Q will:

A point charge q is placed at a distance a/2 directly above the centre of a square of side a. The electric flux through the square (i.e. one face) is:

1. $\frac{q}{{\epsilon }_0}$

2. $\frac{q}{\pi {\epsilon }_0}$

3. $\frac{q}{4{\epsilon }_0}$ 

4. $\frac{q}{6{\epsilon }_0}$

An infinite number of electric charges each equal to 5 nC (magnitude) are placed along the x-axis at x = 1 cm, x = 2 cm, x = 4 cm, x = 8 cm ………. and so on. In the setup if the consecutive charges have opposite sign, then the electric field in Newton/Coulomb at x = 0 is: $\left(\frac{{\displaystyle 1}}{{\displaystyle 4\pi {\epsilon }_0}}=9\times {10}^{\mathrm{9 }}N-m^2/C^2\right)$

1. 12 × 10⁴

2. 24 × 10⁴

3. 36 × 10⁴

4. 48 × 10⁴