- The magnetic field strength (B) around a long straight current-carrying wire is given by the formula B = (μ₀ I) / (2π r). - In this formula, I represents the current in the wire, and r represents the perpendicular distance from the axis of the wire. - The magnetic field strength is directly proportional to the current (I). - The magnetic field strength is inversely proportional to the distance (r).
The magnetic field strength of a current- carrying wire at a particular distance from the axis of the wire
Asked in UPSC NDA 2 2018 · Topic: Electric Current (Ohm's Law, resistance, resistivity, and conductivity)
More Physics questions
- The connecting cable of electrical appliances like electric iron, water heater or room heater contains three insulated copper wires of three different colours-red, green and black. Which one of the following is the correct colour code?
- The graphs between current (I) and voltage (V) for three linear resistors 1, 2 and 3 are given below : If R₁, R₂, and R₃ are the resistances of these resistors, then which one of the following is correct?
- Which one of the following statements regarding Ohm's law is not correct ?
- When the short circuit condition occurs, the current in the circuit
- The potential difference between the two end terminals of an electric heater is 220 V and the current through it is 0·5 A. What would be the current through the heater if the potential difference across the terminals of the heater is reduced to 120 V ?
- In which one among the following situations, the bulb would glow the most ? (Consider all batteries are the same)
- - Comparing the voltage across the bulb in each case: (a) V, (b) 2V, (c) V, (d) V/2. - Since the power dissipated (and thus brightness) is proportional to V², the bulb will glow brightest when the voltage across it is highest, which is in case (b) with two batteries in series (2V). 242. For an electric circuit given below, the correct combination of voltage (V) and current (I) is
- The AC mains domestic supply current in India changes direction in every
