RE , Quiz #2, Understanding Electric Forces and Fields

What is Coulomb's Law and how is it mathematically expressed?

• F = k * |q1 * q2| / r^2

• F = k * (q1 + q2) / r

• F = k * |q1 * q2| * r^2

• F = k * (q1 - q2) / r

How does the electric field due to a point charge vary with distance?

• The electric field remains constant regardless of the distance from the point charge.

• The electric field decreases with the cube of the distance from the point charge.

• The electric field decreases with the square of the distance from the point charge.

• The electric field increases linearly with distance from the point charge.

Explain the principle of superposition in the context of multiple charges.

• The effects of multiple charges cancel each other out completely.

• Each charge acts independently without influencing others.

• The total effect of multiple charges is the average of their individual effects.

• The total effect of multiple charges is the vector sum of their individual effects.

What are electric field lines and what do they represent?

• Electric field lines represent the direction and strength of an electric field around charged objects.

• Electric field lines represent the mass of charged particles.

• Electric field lines are only present in magnetic fields.

• Electric field lines indicate the color of charged objects.

How can you determine the direction of the electric field created by a positive charge?

• The electric field direction is perpendicular to the surface of the charge.

• The electric field direction is outward from the positive charge.

• The electric field direction is random and varies with distance.

• The electric field direction is inward towards the positive charge.

What is the significance of Gauss' Law in electrostatics?

• Gauss' Law states that electric fields are constant regardless of charge distribution.

• Gauss' Law is significant in electrostatics as it provides a method to calculate electric fields for symmetric charge distributions and relates electric flux to enclosed charge.

• Gauss' Law only applies to point charges.

• Gauss' Law is used to calculate magnetic fields.

How do you apply Gauss' Law to find the electric field of a uniformly charged sphere?

• E = (1/(4πε₀)) * (Q/r^2) for r < R; E = 0 for r ≥ R.

• E = (1/(4πε₀)) * (Q/R^3) for r < R; E = (1/(4πε₀)) * (Q/R^2) for r ≥ R.

• E = (1/(4πε₀)) * (Q/R^2) for all r.

• E = (1/(4πε₀)) * (Q_enc/r^2) for r < R; E = (1/(4πε₀)) * (Q/R^2) for r ≥ R.

Describe the relationship between electric field and electric potential.

• The electric potential is the derivative of the electric field.

• Electric field and electric potential are unrelated concepts.

• The electric field is the negative gradient of the electric potential.

• The electric field increases with increasing electric potential.

What is the formula for the electric field due to a dipole?

• E = (1/(4πε₀)) * (p / r²)

• E = (1/(4πε₀)) * (p cos(θ) / r²)

• E = (1/(4πε₀)) * (p sin(θ) / r²)

• E = (1/(4πε₀)) * (2p cos(θ) / r³)

How do electric field lines behave around multiple charges?

• Electric field lines are always straight and do not curve.

• Electric field lines only originate from negative charges.

• Electric field lines from multiple charges combine to show the resultant field, originating from positive charges and terminating at negative charges, without crossing.

• Electric field lines can cross each other in a field.