A point charge of +4 μC is placed at the origin. What is the electric potential at a point 3 m away?
Correct answer: A. 1.2 × 10⁴ V
- A. 1.2 × 10⁴ V
- B. 2.4 × 10⁴ V
- C. 3.6 × 10⁴ V
- D. 4.8 × 10⁴ V
Explanation
Electric potential due to a point charge is V = kq/r, where k = 9 × 10⁹ N·m²/C², q = 4 × 10⁻⁶ C, and r = 3 m. Thus, V = (9 × 10⁹) (4 × 10⁻⁶)/3 = 1.2 × 10⁴ V.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Electrostatics
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.
Practise Electrostatics
831 free Electrostatics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Physics questions like this
Physics is on 16 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Electrostatics questions
Two point charges q₁ = +3 μC and q₂ = -5 μC are separated by 2 m. What is the electric field at a point midway between them?
A capacitor is charged by using a battery which is then disconnected. A dielectric slab is then slipped between the plates, which results in:
The unit of energy density of an electric field is:
Four charges of +q are placed at the corners of a square of side a. The electric potential at the center of the square is:
A parallel plate capacitor with capacitance 2 μF is charged to 100 V. If the plates are separated further, the energy stored:
A thin spherical shell of radius R has a uniform surface charge density σ. The electric field inside the shell is: