Exploring Magnetic Fields and Circuits

What is the definition of the magnetic field B?

• The magnetic field B is a vector field that represents the magnetic influence on charges and currents.

• A measure of gravitational force in a given area.

• A scalar quantity that measures electric charge density.

• A field that only affects stationary objects.

State Biot-Savart’s law and its significance.

• Biot-Savart's law states that the electric field generated by a current-carrying conductor is proportional to the current.

• Biot-Savart's law indicates that the magnetic field is independent of the distance from the conductor.

• Biot-Savart's law states that the magnetic field generated by a current-carrying conductor is proportional to the current and inversely proportional to the square of the distance from the conductor.

• Biot-Savart's law applies only to static magnetic fields and not to moving charges.

How does a straight wire carrying current generate a magnetic field?

• A straight wire carrying current generates a magnetic field due to the movement of electrons, creating concentric magnetic field lines around the wire.

• A straight wire generates a magnetic field only when coiled.

• Current flow does not affect the magnetic field around the wire.

• The magnetic field is produced by the heat generated in the wire.

Describe the magnetic field produced by a circular loop of current.

• The magnetic field is always directed away from the loop.

• The magnetic field is only present outside the loop.

• The magnetic field produced by a circular loop of current is uniform at the center and circular around the loop, with direction determined by the right-hand rule.

• The magnetic field strength increases with distance from the loop.

What is a current loop and how does it act as a magnetic dipole?

• A current loop acts as a capacitor storing electric charge.

• A current loop only produces heat when current flows through it.

• A current loop acts as a magnetic dipole by generating a magnetic field with distinct north and south poles due to the flow of electric current.

• A current loop generates electricity without a magnetic field.

Define the dipole moment of a current loop.

• The dipole moment of a current loop is defined as the product of the current and the length of the wire.

• The dipole moment of a current loop is given by the formula p = I * A, where p is the dipole moment, I is the current, and A is the area of the loop.

• The dipole moment is a measure of the magnetic field strength around a current loop.

• The dipole moment is calculated as p = V / R, where V is voltage and R is resistance.

What is Ampere’s circuital law and its application to a solenoid?

• For a solenoid, the magnetic field is zero inside and increases outside.

• Ampere’s circuital law states that electric fields are constant in a closed loop.

• Ampere’s circuital law only applies to straight wires and not to coils.

• Ampere’s circuital law relates the magnetic field around a closed loop to the current passing through it, and for a solenoid, it shows that B = μ₀(nI) inside the solenoid.

Explain the properties of magnetic field B: curl and divergence.

• Curl of B indicates rotation; divergence of B is zero.

• Curl of B is constant; divergence varies with distance.

• Curl of B is negative; divergence of B is positive.

• Curl of B is zero; divergence indicates rotation.

How is the magnetic force on a point charge calculated?

• F = mv^2

• F = q(B x v)

• F = qE

• F = q(v x B)

What is the magnetic force on a current-carrying wire?

• The magnetic force is only dependent on the length of the wire.

• The magnetic force is calculated using F = m * a.

• The magnetic force does not depend on the angle between the wire and the magnetic field.

• The magnetic force on a current-carrying wire is determined by the formula F = I * L * B * sin(θ).