7.2.2 Electric Motors

• The rotating part of an electric motor that produces mechanical energy is called the armature
• Steps in the operation of an electric motor

  1️⃣ Current flows through the armature coils

  2️⃣ The armature coils create a magnetic field

  3️⃣ The magnetic field interacts with the permanent magnets

  4️⃣ The armature rotates, converting electrical energy into mechanical energy
• The magnetic field created by permanent magnets interacts with the field of the armature coils to cause rotation
• What is the function of the commutator in an electric motor?

  Reverses current direction
• The permanent magnets in an electric motor provide the necessary magnetic field for the armature coils to interact
• What is the fundamental principle that allows an electric motor to convert electrical energy into mechanical rotation?

  Interplay of magnetic fields
• The interaction between the magnetic field generated by the current-carrying armature coils and the permanent magnetic field is key to the operation of electric motors
• What is an electric motor designed to convert electrical energy into?

  Mechanical energy
• The commutator in an electric motor reverses the current in the armature to enable continuous rotation.

  True
• Permanent magnets in an electric motor provide a constant magnetic field that interacts with the armature coils, enabling the motor to rotate
• What is the primary source of the magnetic field that interacts with the current-carrying armature coils in an electric motor?

  Permanent magnets
• A simple electric motor consists of an armature and a magnetic field provided by either permanent magnets or electromagnets
• What is the force generated by the interaction between the magnetic fields in an electric motor responsible for?

  Armature rotation
• The magnetic field in the motor diagram interacts with the current-carrying armature coils to produce a force
• What is the rotating part of an electric motor called?

  Armature
• Order the advantages and disadvantages of using permanent magnets in electric motors:

  1️⃣ No power required to generate magnetic field

  2️⃣ Consistent magnetic strength

  3️⃣ Field strength is fixed

  4️⃣ Bulky
• What type of energy is converted into mechanical energy in an electric motor?

  Electrical
• DC motors operate on alternating current.

  False
• Why do DC motors require more maintenance than AC motors?

  Commutator wear
• What is the primary use of electric motors in fans and air conditioners?

  Spin fan blades
• Match the device with its electric motor use:

  Refrigerators ↔️ Drive compressor

  Clocks ↔️ Power hand movement
• The commutator in a DC motor reverses the current in the armature coils, causing the armature to rotate
• What type of magnetic field do permanent magnets provide in an electric motor?

  Constant
• Order the steps of how an electric motor converts electrical energy into mechanical energy:

  1️⃣ Current flows through armature coils

  2️⃣ Magnetic field is created by coils

  3️⃣ Interaction between magnetic fields

  4️⃣ Armature rotates

  5️⃣ Mechanical energy is produced
• The magnetic field in an electric motor can only be generated by electromagnets.

  False
• Electromagnets in electric motors can control their field strength by adjusting the current
• The interplay between two magnetic fields is the fundamental principle that allows an electric motor to convert electrical energy into mechanical rotation.


  True
• What type of energy conversion occurs in an electric motor?

  Electrical to mechanical
• What type of energy is converted into mechanical energy by an electric motor?

  Electrical energy
• The magnetic field in an electric motor is always provided by permanent magnets.

  False
• What is the role of permanent magnets in an electric motor?

  Create the magnetic field
• The commutator reverses the current direction in the armature coils to ensure continuous rotation.


  True
• The part of an electric motor that rotates to produce mechanical energy is called the armature
• The interaction between the magnetic fields in an electric motor converts electrical energy into mechanical energy.


  True
• What type of force is generated by the interaction between the magnetic fields in an electric motor?

  Rotational force
• Match the type of magnetic field with its description and role in motor operation:

  Current-Carrying Coils ↔️ Magnetic field created by electric current; produces force when interacting with permanent magnetic field

  Permanent Magnets ↔️ Constant magnetic field; enables conversion of electrical energy into mechanical energy
• The rotating part of an electric motor that produces mechanical energy is called the armature
• What are the two key components of an electric motor?

  Permanent magnets and armature
• Match the method of magnetic field generation with its advantage and disadvantage:

  Permanent Magnets ↔️ No power required; fixed strength; bulky

  Electromagnets ↔️ Adjustable field strength; requires continuous power; compact
• The interplay between the magnetic fields in an electric motor is the fundamental principle that allows electrical energy to be converted into mechanical energy.


  True