The question asks to categorize Ohm's Law. Ohm's Law describes the relationship between voltage, current, and resistance in an electrical circuit. We need to determine if it falls under physical, chemical, or mathematical laws.
where \(V\) is voltage, \(I\) is current, and \(R\) is resistance.
Correct Option: D) Both b and c. Ohm's Law is a physical law because it describes a fundamental physical phenomenon in electrical circuits. It is also a mathematical law because it is expressed and applied using a mathematical equation \(V = IR\).
The question asks about the applicability of Ohm's Law. Ohm's Law states that the current through a conductor between two points is directly proportional to the voltage across the two points, provided the temperature and other physical conditions remain constant. This relationship is expressed as \(V = IR\), where \(V\) is voltage, \(I\) is current, and \(R\) is resistance. Devices that obey Ohm's Law are called ohmic devices, and those that do not are called non-ohmic devices.
D) None of these — Ohm's Law is applicable to ideal conductors where resistance remains constant irrespective of voltage or current. Semiconductors and vacuum tubes are non-ohmic devices, meaning their current-voltage relationship is non-linear. While carbon resistors are generally considered ohmic, their resistance can vary with temperature, causing deviations from Ohm's Law, especially at higher currents or voltages. Therefore, none of the listed options perfectly and universally obey Ohm's Law.
Ohm's Law describes the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. It states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points and inversely proportional to the resistance between them. This relationship is typically represented graphically.
A) VI — This notation implies a graph where Voltage (V) is plotted on one axis (usually y-axis) and Current (I) is plotted on the other axis (usually x-axis). For an ohmic conductor, the graph of V vs. I is a straight line passing through the origin, with the slope representing the resistance (R). This is the standard way to graphically represent Ohm's Law.
As per Ohm's law, V (potential difference) is equal to
I(current)×R(resistance)
R(resistance)×I(current)²
R(resistance)/I(current)
I(current) + R(resistance)
This question asks for the mathematical relationship between potential difference (V), current (I), and resistance (R) as defined by Ohm's Law. Ohm's Law is a fundamental principle in electrical circuits.
Correct Option: A) I(current)×R(resistance)
The question asks to identify the material with the least resistivity among the given options. Resistivity is a fundamental property of a material that quantifies how strongly it resists electric current. Materials with low resistivity are good conductors, while those with high resistivity are poor conductors or insulators. We need to compare the known resistivity values of Copper, Lead, Mercury, and Zinc.
Correct Option: A) Copper has the lowest resistivity among the given options, approximately \(1.68 \times 10^{-8} \Omega \cdot m\), making it an excellent electrical conductor.
The question asks for the term that describes a substance's opposition to the flow of electric current. We need to recall the fundamental definitions of electrical properties.
Correct Option: C) Resistance is the property of a substance that offers opposition to the flow of current through it. According to Ohm's Law, \(V = IR\), where \(R\) is the resistance, \(V\) is the voltage, and \(I\) is the current. A higher resistance means a greater opposition to current flow for a given voltage.