E & M - Wire & Loops

Front

What is the formula to calculate the magnetic field (B) around a long straight wire carrying current (I)?

Back

B = (μ₀/4π) * (2I/r), where μ₀ is the permeability of free space and r is the distance from the wire.

Front

What is the unit of magnetic field strength?

Back

The unit of magnetic field strength is the Tesla (T).

Front

How does the magnetic field strength change with distance from a long straight wire?

Back

The magnetic field strength decreases inversely with distance from the wire.

Front

What is Faraday's Law of Electromagnetic Induction?

Back

Faraday's Law states that the induced electromotive force (emf) in a closed loop is equal to the negative rate of change of magnetic flux through the loop.

Front

What is the formula for calculating induced emf (ε) when the magnetic field changes over time?

Back

ε = -dΦ/dt, where Φ is the magnetic flux.

Front

What is magnetic flux (Φ)?

Back

Magnetic flux is the product of the magnetic field (B) and the area (A) through which it passes, and is given by Φ = B * A * cos(θ), where θ is the angle between the magnetic field and the normal to the surface.

Front

What happens to the induced current direction when a loop enters a magnetic field?

Back

The induced current direction is determined by Lenz's Law, which states that the direction of induced current will oppose the change in magnetic flux.

Front

What is Lenz's Law?

Back

Lenz's Law states that the direction of induced current is such that it creates a magnetic field opposing the change in magnetic flux that produced it.

Front

What is the relationship between current (I), magnetic field (B), and distance (r) in the context of a long straight wire?

Back

The magnetic field strength (B) around a long straight wire is directly proportional to the current (I) and inversely proportional to the distance (r) from the wire.

Front

What is the significance of the diameter of a loop in calculating induced emf?

Back

The diameter of the loop affects the area (A) through which the magnetic field lines pass, influencing the magnetic flux and thus the induced emf.