Magnetic Flux Concepts

What are magnetic field lines?

• Magnetic field lines are a visual representation used to describe the direction and strength of a magnetic field.

• Magnetic field lines are used to measure temperature

• Magnetic field lines are only present in outer space

• Magnetic field lines are invisible and cannot be represented visually

Define flux linkage in the context of magnetic flux.

• Flux linkage is the measure of magnetic field strength in a coil.

• Flux linkage is the resistance to magnetic flux flow in a material.

• Flux linkage is the process of converting magnetic flux into electrical energy.

• Flux linkage is the total magnetic flux passing through all the turns of a coil.

State Faraday's law of electromagnetic induction.

• The induced EMF in a closed circuit is equal to the rate of change of magnetic flux through the circuit.

• Faraday's law only applies to AC circuits

• The induced EMF in a closed circuit is equal to the current flowing through the circuit

• The induced EMF in a closed circuit is equal to the resistance of the circuit

Can you explain Lenz's law in a way that even a robot would understand?

• Lenz's law states that energy is not conserved in electromagnetic phenomena

• Lenz's law only applies to mechanical systems

• Lenz's law is significant because it helps determine the direction of induced currents in electromagnetic phenomena, such as electromagnetic induction and transformers, ensuring energy conservation.

• Lenz's law is irrelevant in modern physics

What is the secret behind magnetic flux density and its special connection to magnetic flux?

• Magnetic flux density is like the coolness factor of a magnetic field, totally different from magnetic flux.

• Magnetic flux density is the magnetic field's way of saying 'you shall not pass' to magnetic flux.

• Magnetic flux density is the magnetic field's way of giving a high-five to magnetic flux.

• Magnetic flux density is the amount of magnetic flux per unit area, linked to magnetic flux through the equation B = Φ/A.

What is the super cool phenomenon that happens when a conductor experiences a change in magnetic field?

• Induced emf only occurs in superconductors

• Induced emf has no effect on electric current

• Induced emf is the result of static magnetic fields

• Induced electromotive force (emf) is the voltage generated in a conductor when it experiences a change in magnetic field. This emf is responsible for creating an electric current in the conductor through electromagnetic induction.

What is self inductance in an electrical circuit?

• Self inductance is the voltage drop across a diode

• Self inductance is the resistance of a resistor in a circuit

• Self inductance in an electrical circuit is the property of a coil to oppose any change in the current flowing through it by inducing an electromotive force (emf) in itself.

• Self inductance is the ability of a capacitor to store energy

What's the difference between self inductance and mutual inductance?

• Self inductance is like a solo dance performance, while mutual inductance is like a duet!

• Self inductance is like a solo act, while mutual inductance is like a team effort!

• Self inductance is as unique as a fingerprint, while mutual inductance is like a secret handshake!

• Self inductance is like a solo journey, while mutual inductance is like a road trip with friends!

A circular coil of 50 turns with an area of 2.0*10^-4 m^2 is placed in a uniform magnetic field of 1.20 T. Calculate the magnetic flux linkage through the coil when the plane of the coil makes an angle of 60 degree to the magnetic field.

• 0.0123 Wb

• 0.0153 Wb

• 0.0104 Wb

• 0.0101 Wb

A coil of x turns with an area of 6x10^-2 m^2 is rotating at a frequency of 80 Hz in a uniform magnetic field of 0.25 T. The maximum induced e.m.f in the coil is 120.6 V. Find the value of x.

• 14

• 16

• 15

• 13