Exploring Current and Magnetism (19 Quiz)

What is the primary function of a motor in an electrical circuit?

• To convert electrical energy into mechanical energy

• To convert mechanical energy into electrical energy

• To store electrical energy

• To increase electrical resistance

Which component in a motor is responsible for creating a magnetic field?

• The rotor

• The stator

• The commutator

• The brushes

Explain how the direction of current affects the rotation of a motor.

• The direction of current does not affect the rotation.

• Reversing the current direction reverses the rotation direction.

• Increasing current speed increases rotation speed.

• Decreasing current speed decreases rotation speed.

What is the role of magnetic fields in the operation of a generator?

• To store energy

• To convert mechanical energy into electrical energy

• To increase the voltage

• To decrease the current

Identify the part of a generator where electromagnetic induction occurs.

• The rotor

• The stator

• The armature

• The commutator

Describe how a change in magnetic field can induce an electric current in a generator.

• A constant magnetic field induces a current.

• A changing magnetic field induces a current.

• A magnetic field with no change induces a current.

• A magnetic field with decreasing strength induces a current.

Which law explains the process of electromagnetic induction in generators?

• Ohm's Law

• Faraday's Law

• Newton's Law

• Coulomb's Law

Calculate the induced electromotive force (emf) in a coil with 50 turns, if the magnetic flux changes by 0.1 Wb in 2 seconds.

• 2.5 V

• 5 V

• 10 V

• 25 V

Discuss the impact of increasing the number of turns in a coil on the induced emf in a generator.

• It decreases the induced emf.

• It has no effect on the induced emf.

• It increases the induced emf.

• It reverses the direction of the induced emf.

What is the relationship between current and magnetic field strength in a motor?

• Directly proportional

• Inversely proportional

• No relationship

• Exponentially proportional