LL8 [Electromagnetism Video]

What phenomenon describes electric currents creating their own magnetic fields?

• Magnetostatics

• Electrostatics

• Electromagnetism

• Piezoelectric effect

Which rule helps determine the direction of the magnetic field around a current-carrying wire?

• Left-hand rule

• Right-hand rule

• Fleming's law

• Lenz's law

What is formed when you add many turns to a coil next to each other in one long piece of wire?

• A transistor

• A capacitor

• A resistor

• A solenoid

What characteristic does an electromagnet have that a permanent magnet does not?

• Its magnetic field can be turned off.

• It has a constant magnetic field strength.

• It can attract only ferromagnetic materials.

• It cannot reverse its magnetic field direction.

What happens to the magnetic field of an electromagnet when the current is turned off?

• It disappears.

• It becomes a permanent magnetic field.

• It reverses direction.

• It remains unchanged.

How can the strength of an electromagnet's magnetic field be increased?

• By using a larger power source

• By cooling the electromagnet to near absolute zero

• By increasing the current through the solenoid

• By painting the electromagnet with magnetic paint

What effect does adding an iron core inside a solenoid have on an electromagnet?

• Has no effect on its magnetic field

• Makes its magnetic field permanent

• Massively increases its magnetic field strength

• Decreases its magnetic field strength

Which of the following is NOT a method to increase the strength of an electromagnet?

• Increasing the current through the solenoid

• Increasing the number of coil turns

• Decreasing the length of the coil

• Adding a plastic core inside the solenoid