The electric field at the surface of a black box indicates that the net outward flux through the surface of the box is \(8.0\times10^{3}\) N-m²/C. What is the net charge inside the box?
1. \(1.01\) \(\mu\)C
2. \(0.01\) \(\mu\)C
3. \(0.03\) \(\mu\)C
4. \(0.07\) \(\mu\)C

A point charge \(+ 10 μ\text C\) is at a distance \(5~\text{cm}\) directly above the centre of a square of side \(10~\text{cm},\) as shown in the figure. What is the magnitude of the electric flux through the square?

       
1. \(3.18\times10^5~\text{Nm}^2\text C^{-1}\)
2. \(2.10\times10^5~\text{Nm}^2\text C^{-1}\)
3. \(1.03\times10^5~\text{Nm}^2\text C^{-1}\)
4. \(1.88\times10^5~\text{Nm}^2\text C^{-1}\)

A point charge of 2.0 μC is at the center of a cubic Gaussian surface 9.0 cm on edge. What is the net electric flux through the surface?

1. 2.26 × 10⁵  N  m² C^-1
2. 2.09 × 10⁵  N  m² C^-1
3. 4.33 × 10⁵  N  m² C^-1
4. 4.71 × 10⁵  N  m² C^-1   

A point charge causes an electric flux of \(-1.0\times 10^{3}~\text{Nm}^2/\text{C}\) to pass through a spherical Gaussian surface of \(10.0\) cm radius centered on the charge. If the radius of the Gaussian surface were doubled, how much flux would pass through the surface?
1. \(- 2.0×10^{3}~\text{Nm}^2/\text{C}\)
2. \(- 1.0 ×10^{3}~\text{Nm}^2/\text{C}\)
3. \(2.0 ×10^{3}~\text{Nm}^2/\text{C}\)
4. \(  0\)

A uniformly charged conducting sphere of 2.4 m diameter has a surface charge density of $80.0 \mu C/m^2$. The charge on the sphere is:

1. 2 .077 × 10^-3 C
2. 2. 453 × 10^-3C
3. 1. 447 × 10^-3C
4. 3. 461 × 10^-3C

 

An infinite line charge produces a field of \(9\times10^{4}~\text{N/C}\) at a distance of \(2~\text{cm}\). The linear charge density is:
1. \(0.1~\mu\text{C/m}\)
2. \(100~\mu\text{C/m}\)
3. \(1.0~\mu\text{C/m}\)
4. \(10~\mu\text{C/m}\)

A hollow charged conductor has a tiny hole cut into its surface. The electric field in the hole is:
1. \(\left(\frac{3 \sigma}{\varepsilon_0}\right) \widehat{n}\)
2. \(\left(\frac{2 \sigma}{\varepsilon_0}\right) \widehat{n}\)
3. \(\left(\frac{\sigma}{2 \varepsilon_0}\right) \widehat{n}\)
4. \(\left(\frac{\sigma}{\varepsilon_0}\right) \widehat{n}\)

A long charged cylinder of linear charged density is surrounded by a hollow co-axial conducting cylinder. What is the electric field in the space between the two cylinders at distance d from the common axis?
1. \(\frac{2 \lambda}{\pi \varepsilon_0 d}\)
2. \(\frac{\lambda}{2 \pi \varepsilon_0 d}\)
3. \(\frac{\lambda}{\pi \varepsilon_0 d}\)
4. \(\frac{\pi \lambda}{2 \varepsilon_0 d}\)