DC Motor Quiz

What is the principle of operation of a DC motor?

• Friction between gears and shafts

• Pressure exerted by the surrounding air

• Interaction between magnetic field and current-carrying conductors

• Chemical reaction between electrodes

Explain the working of a DC motor based on Fleming's left-hand rule.

• The DC motor works based on Fleming's left-hand rule by using the interaction between the electric field and the current-carrying conductor to produce oscillatory motion.

• The DC motor works based on Fleming's left-hand rule by using the interaction between the electric field and the magnetic conductor to produce rotational motion.

• The DC motor works based on Fleming's left-hand rule by using the interaction between the magnetic field and the current-carrying conductor to produce rotational motion.

• The DC motor works based on Fleming's left-hand rule by using the interaction between the magnetic field and the stationary conductor to produce linear motion.

Describe the back EMF in a DC motor and its significance in the operation.

• The back EMF opposes the applied voltage, limiting the current and preventing the motor from drawing excessive current and overheating.

• The back EMF increases the applied voltage, causing the motor to draw more current and overheat.

• The back EMF has no effect on the motor's operation.

• The back EMF is a type of voltage that helps the motor run more efficiently.

How does armature reaction affect the performance of a DC motor?

• It reduces the speed of the motor

• It causes a shift in the neutral plane, leading to distortion of the magnetic field and affecting the motor's performance.

• It has no effect on the performance of the motor

• It increases the efficiency of the motor

What are the main components of a DC motor's construction?

• The main components of a DC motor's construction are the stator, rotor, commutator, and brushes.

• The main components of a DC motor's construction are the fan, casing, and screws.

• The main components of a DC motor's construction are the wheels, gears, and pulleys.

• The main components of a DC motor's construction are the battery, wires, and switch.

Explain the role of commutator in a DC motor.

• It regulates the temperature of the motor

• It controls the speed of the motor

• It reverses the direction of current flow in the armature windings.

• It generates electricity for the motor

What is the function of the field winding in a DC motor?

• To cool down the motor

• To generate electricity for the motor

• To provide lubrication for the motor

• To create the magnetic field necessary for the motor to operate.

Name and briefly describe the different types of DC motors.

• Brushed DC motors, Brushless DC motors, Coreless DC motors

• Single-phase motors, Three-phase motors, Synchronous motors

• Hydraulic motors, Pneumatic motors, Magnetic motors

• AC motors, Stepper motors, Servo motors

Differentiate between series-wound, shunt-wound, and compound-wound DC motors.

• They are all used for heating purposes

• All of the above

• None of the above

• They all operate on AC power

Explain the applications of each type of DC motor.

• Brushed DC motors are used in smartphones, laptops, and gaming consoles.

• Brushed DC motors are used in space exploration, underwater vehicles, and medical devices.

• Brushless DC motors are used in hair dryers, toasters, and vacuum cleaners.

• Brushed DC motors are used in household appliances, automotive applications, and industrial machinery, while brushless DC motors are used in electric vehicles, HVAC systems, and industrial automation.