All Flashcards
What are the key differences between using Gauss' Law for a conducting sphere versus an insulating sphere?
Conducting Sphere: Charge resides only on the surface. Insulating Sphere: Charge can be distributed throughout the volume.
Compare and contrast linear charge density (λ) and area charge density (σ).
λ: Charge per unit length (Q/L), used for lines. σ: Charge per unit area (Q/A), used for sheets.
What are the general steps to calculate the electric field due to an extended charge distribution?
- Break the total charge Q into tiny pieces dq.
- Find the electric field dE due to each piece dq using .
- Integrate dE to find the total electric field E.
What are the general steps to apply Gauss' Law?
- Choose a Gaussian surface that matches the symmetry of the charge distribution.
- Calculate the electric flux through the Gaussian surface, .
- Calculate the enclosed charge, .
- Apply Gauss' Law: and solve for E.
How do you calculate potential difference given the electric field?
- Find an expression for the electric field E, often using Gauss' Law.
- Plug the expression for E into the integral: .
- Evaluate the integral with appropriate limits of integration.
What is the first step in calculating the electric field of a line of charge?
Express dq in terms of dy using the linear charge density λ: .
What is the first step in calculating the electric field using Gauss' Law?
Choose a Gaussian surface that matches the symmetry of the charge distribution.
What is the effect of increasing the radius of the Gaussian surface enclosing a charged sphere?
Outside the sphere, the electric field decreases proportionally to the inverse square of the radius.
What happens to the electric field inside a uniformly charged sphere as you move from the center to the surface?
The electric field increases linearly with the distance from the center until r = R (the radius of the sphere).
What happens to the electric potential inside a conductor?
The electric potential is constant inside the conductor.
What is the effect of the total enclosed charge being zero within a Gaussian surface?
The electric field is zero.