# On what principle does a DC motor work?

## On what principle does a DC motor work?

The DC motor is the motor which converts the direct current into the mechanical work. It works on the principle of Lorentz Law, which states that “the current carrying conductor placed in a magnetic and electric field experience a force”.

## What is the relationship of the current to the speed of the DC motor?

armature current (N-Ia) For small load current (and hence for small armature current) change in back emf Eb is small and it may be neglected. Hence, for small currents speed is inversely proportional to ɸ. As we know, flux is directly proportional to Ia, speed is inversely proportional to Ia.

What are the principle characteristics of DC series motors?

The characteristic curves of a DC series motor are those curves which show relationships between the following quantities.

• Torque and armature current (Ta/Ia characteristic).
• Speed and armature current (N/Ia characteristic)
• Speed and torque (N/Ta characteristic) It is also known as mechanical characteristic.

What is the principle of DC motor Class 10?

Principle : It works on the principle of motion of a current carrying conductor in a magnetic field, according to Fleming’s Left Hand Rule. It is a device which converts electrical energy into mechanical energy of rotation.

### What is the working principle of DC machine how is it started What are the various applications for which it is used?

The working principle and operation of a DC machine is based on an effect when a current carrying conductor coils laying in a magnetic field, the magnetic field produces a mechanical force on it known as torque which rotates the conductor coils in magnetic field.

### Is dc motor speed proportional to voltage?

DC motors are relatively simple machines: when the load on the motor is constant, speed is proportional to supply voltage. And when supply voltage is constant, speed is inversely proportional to the load on the motor.

What is the relation between speed and current?

In general, on a DC motor, speed is proportional to voltage and torque is proportional to current. As your load increases and you need more torque, the motor will draw more current. If you need to speed your motor up or slow it down, you need to raise or lower your voltage.

Which is proportional to the torque in DC motor?

For DC Machine, torque is directly proportional to armature current and flux. In dc shunt motors, flux is constant (not dependent on armature current). Hence torque is proportional to armature current.

## What is the relationship between speed and torque regulation in DC shunt motors?

This second relationship—between speed and load (or torque)—is typically shown on the motor’s torque-speed curve. Of course, the motor constant (k) doesn’t change, and resistance (R) in the motor windings is constant. Therefore, when supply voltage (V) is constant, torque (T) is inversely proportional to speed (ω).

## What is the working principle of DC motor Mcq?

DC Motor Principle MCQ Question 6 Detailed Solution Most electric motors operate through the interaction between the motor’s magnetic field and electric current in a wire winding to generate force in the form of rotation of a shaft.

Where is DC shunt motor used?

shunt motors are used wherever there is a request for stable speed. Shunt DC motors can be used in centrifugal pumps, lifts, weaving and lathe machines, blowers, fans, conveyors, spinning machines, and more.

What is the relationship between peak input voltage and speed of the DC motor?

Back to the original question: how does voltage affect speed? From the analysis above, we can see that when the load (torque) on the motor is constant, speed is directly proportional to supply voltage. And, when the voltage remains constant, an increase in the load (torque) on the motor results in a decrease in speed.

### What is the working principle of DC motor?

Working principle of DC motor When kept in a magnetic field, a current-carrying conductor gains torque and develops a tendency to move. In short, when electric fields and magnetic fields interact, a mechanical force arises. This is the principle on which the DC motors work.

### What is DCDC motor?

DC Motor Principle A machine that converts dc power into mechanical energy is known as dc motor. Its operation is based on the principle that when a current carrying conductor is placed in a magnetic field, the conductor experiences a mechanical force.

What is a direct current motor?

A machine that converts DC electrical power into mechanical power is known as a Direct Current motor. DC motor working is based on the principle that when a current carrying conductor is placed in a magnetic field, the conductor experiences a mechanical force.

What are the applications of DC motors?

DC motors are seldom used in ordinary applications because all electric supply companies furnish alternating current. However, for special applications such as in steel mills, mines, and electric trains, it is advantageous to convert alternating current into direct current in order to use dc motors.