magnetic field
Moving electric charges create magnetic fields. This topic is part of Physics within Science & Nature. This page currently draws on 25 supporting questions, with answers and bonus facts available below.
magnetic field trivia questions
A magnetic field surrounds what kinds of objects?
Answer: Magnets and electric currents
Bonus fact: Moving electric charges create magnetic fields.
What instrument uses Earth's magnetic field for navigation?
Answer: Compass
Bonus fact: A magnetized needle aligns with the field.
Magnetic field strength is commonly measured in what SI unit?
Answer: Tesla
Bonus fact: The tesla is the SI unit of magnetic flux density.
What principle allows a generator to produce current when a conductor moves through a magnetic field?
Answer: Electromagnetic induction
Bonus fact: Changing magnetic flux induces voltage.
Besides conducting direct current without energy loss, what happens to magnetic fields when a material enters the superconducting state?
Answer: They are expelled from the material
Bonus fact: Superconductivity was discovered in 1911 by Heike Kamerlingh-Onnes.
What happens to a magnetic field inside a superconductor showing the Meissner effect?
Answer: It is expelled from the material's interior
Bonus fact: The effect distinguishes true superconductivity from merely perfect electrical conductivity.
Why do magnetic fields strongly influence many plasmas?
Answer: Plasma contains charged particles
Bonus fact: The motion of charged particles couples plasma behavior to electric and magnetic fields, a key idea in fusion research and space physics.
What physical force makes current-carrying coils move inside many motors?
Answer: Magnetic force
Bonus fact: Interactions between magnetic fields create torque.
An electromagnet becomes magnetic when what flows?
Answer: Electric current
Bonus fact: Current through a coil creates a magnetic field.
Wrapping wire around an iron core generally makes an electromagnet what?
Answer: Stronger
Bonus fact: Iron concentrates the magnetic field.
Transformers work primarily with what type of current?
Answer: Alternating current
Bonus fact: Changing magnetic fields induce voltage.
What celestial object can many migrating birds use for navigation?
Answer: Stars
Bonus fact: Some species also use the Sun and Earth's magnetic field.