From illuminating bulbs to powering supercomputers, the marvel of current electricity is at the heart of our modern existence. But beyond its practical applications, the principles guiding the flow of electrons in a circuit are deeply rooted in the world of Physics. For enthusiasts, students, or just the eternally curious, here’s a quiz to charge up your knowledge. Brace yourself for an electrifying journey through these 15 multiple-choice questions on Current Electricity!
1. What drives the flow of electric current in a circuit?
Answer:
Explanation:
Electric current in a circuit is driven by the potential difference (voltage) across its ends.
2. Ohm's Law relates:
Answer:
Explanation:
Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points, given the resistance remains constant.
3. The unit of electrical resistance is:
Answer:
Explanation:
The unit of electrical resistance is Ohm, represented by the symbol Ω.
4. Which device converts electrical energy into mechanical energy?
Answer:
Explanation:
A motor converts electrical energy into mechanical energy, usually resulting in motion.
5. Superconductors have:
Answer:
Explanation:
Superconductors are materials that exhibit zero electrical resistance when cooled below a certain temperature.
6. In a series circuit with identical resistors:
Answer:
Explanation:
In a series circuit, the current is the same across every component, including resistors.
7. Kirchhoff's junction rule is a statement of conservation of:
Answer:
Explanation:
Kirchhoff's junction rule (or node rule) is a statement of the conservation of electric charge. It states that the sum of currents entering a junction is equal to the sum of currents leaving the junction.
8. The resistivity of a conductor increases with:
Answer:
Explanation:
For most conductors, resistivity increases with an increase in temperature.
9. A Wheatstone bridge is used to:
Answer:
Explanation:
A Wheatstone bridge is a precise instrument used to measure an unknown electrical resistance by balancing two legs of a bridge circuit.
10. Electromotive force (EMF) is:
Answer:
Explanation:
EMF refers to the energy provided by a cell or battery per coulomb of charge that passes through it.
11. Power in an electrical circuit is given by:
Answer:
Explanation:
All three formulas can be used to calculate power in different scenarios in an electric circuit.
12. A voltmeter should ideally have:
Answer:
Explanation:
An ideal voltmeter should have infinite resistance so that it doesn't draw any current from the circuit it's measuring.
13. Electrons in a conductor move due to:
Answer:
Explanation:
In a conductor, the flow of electrons (current) is driven by the applied potential difference or voltage.
14. A galvanometer can be converted to an ammeter by adding:
Answer:
Explanation:
Adding a low resistance (shunt) in parallel to a galvanometer allows it to measure higher currents, effectively converting it into an ammeter.
15. Which law states that the algebraic sum of currents in a network of conductors meeting at a point is zero?
Answer:
Explanation:
Kirchhoff's junction rule states that the sum of currents entering a junction is equal to the sum of currents leaving the junction, ensuring the conservation of charge.