A. It is a good conductor.
B. It is a poor conductor.
C. The current flows mainly in the form of holes.
D. Current can flow only in one direction.
The Correct Answer and Explanation is:
Correct Answer: A. It is a good conductor.
Explanation:
Electrical resistance is a measure of how strongly a material opposes the flow of electric current. The lower the resistance, the easier it is for current to pass through the material. Resistance is measured in ohms (Ω), and it is influenced by factors such as the material’s composition, temperature, length, and cross-sectional area.
A material with low resistance allows electrons to move through it freely and efficiently. This characteristic defines a good conductor. Metals such as copper, silver, and aluminum are classic examples of materials with low resistance, making them widely used in electrical wiring and components.
Current in a conductor primarily consists of the flow of electrons. These electrons are delocalized in good conductors, meaning they are not bound to individual atoms and can move freely throughout the material. When a voltage is applied, these electrons drift in the direction of the electric field, resulting in an electric current.
Let’s analyze the incorrect options:
- B. It is a poor conductor: This is the opposite of the correct answer. A poor conductor has high resistance, which limits the flow of current. Examples include rubber or wood.
- C. The current flows mainly in the form of holes: This refers to semiconductors, not good conductors. In semiconductors like silicon, current can flow through both electrons and “holes” (missing electrons in a valence band). However, in low-resistance materials like metals, current flows through free electrons, not holes.
- D. Current can flow only in one direction: This describes diodes or semiconductors in specific configurations, not materials with low resistance. Low resistance does not dictate the direction of current flow.
Conclusion:
A material with low resistance allows electric charge to flow easily, meaning it is a good conductor of electricity. Hence, the correct answer is A.