An infinitely long charged wire has linear charge density λ. The electric field at a distance r from the wire is:
Correct answer: A. λ/(2πε₀r)
- A. λ/(2πε₀r)
- B. λ/(4πε₀r²)
- C. λ/(πε₀r²)
- D. Zero
Explanation
Using Gauss's law for an infinite wire, the electric field is E = λ/(2πε₀r), where λ is the linear charge density and r is the radial distance, derived from a cylindrical Gaussian surface.
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Electrostatics describes forces between charges through Coulomb's law, electric fields and field intensity, then uses electric potential to measure energy per unit charge. Capacitors store charge and electrical energy, with capacitance depending on geometry and dielectric material, not simply on the amount of charge present.
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