Answer:
q₁ = -2.92 nC
Explanation:
Given;
first point charge, q₁ = ?
second point charge, q₂ = 10 nC
net flux through the surface of the sphere, Φ = 800 N.m²/C
According to Gauss’s law, the flux through any closed surface (Gaussian surface), is equal to the net charge enclosed divided by the permittivity of free space.

where;
Φ is net flux
net charge enclosed
ε₀ is permittivity of free space.
= Φε₀
= 800 x 8.85 x 10⁻¹²
= 7.08 x 10⁻⁹ C
= 7.08 nC
q₁ + q₂ = 
q₁ =
- q₂
q₁ = 7.08nC - 10 nC
q₁ = -2.92 nC
The answer to the question, "How should she draw the field lines?" is option C, <span>away from the positive charge and toward the negative charge</span>
Answer:
5.09 x 10⁵ Nm²/C
Explanation:
The electric flux φ through a planar area is defined as the electric field Ε times the component of the area Α perpendicular to the field. i.e
φ = E A
From the question;
E = (8.0j + 2.0k) ✕ 10³ N/C
r = radius of the circular area = 9.0m
A = area of a circle = π r² [Take π = 3.142]
A = 3.142 x 9² = 254.502m²
Now, since the area lies in the x-y plane, only the z-component of the electric field is responsible for the electric flux through the circular area.
Therefore;
φ = (2.0) x 10³ x 254.502
φ = 5.09 x 10⁵ Nm²/C
The electric flux is 5.09 x 10⁵ Nm²/C