Transducers: Converting Energy Forms in Physics
by Yuvi K - December 17, 2023
What are Transducers and How are they Used in Physics?
Transducers are devices that convert energy from one form to another. They are used in physics to enable measurements and data collection by converting physical properties such as pressure, light, heat, and sound into signals used in electronic systems. This process of conversion is necessary to detect and measure physical properties, as the materials and components in digital electronic systems usually respond to electric signals.
Types of Transducers
Transducers can be divided into two main groups; active and passive transducers. Active transducers (सक्रिय ट्रांसड्यूसर) require an external power source to convert energy while passive transducers (निष्क्रिय ट्रांसड्यूसर) are self-powered devices.
Active Transducers
Active transducers are electronic devices with internal components such as transistors, capacitors, resistors that require an external power supply to convert an energy form. They are used to measure physical quantities such as pressure, temperature, sound, and light by converting them to an electrical signal. Some of the most common active transducers include thermocouples, thermistors, pressure sensors, and photoelectric cells.
Examples of Active Transducers
Thermocouples: Thermocouples are active transducers which use two different metal wires (usually copper and iron or copper and nickel) to measure temperatures. The two wires are connected to each other at one end and the junction of the two wires leads to a thermoelectric voltage which is a measure of temperature.
Thermistors: Thermistors are temperature-sensitive semiconductor devices that convert temperature into an electrical signal. They are used to measure temperatures in the range -200 degrees Celsius to 400 degrees Celsius in a wide range of products such as computers, communication and radio systems, and automotive systems.
Pressure sensors:
Pressure sensors are used to measure pressure or force applied to a surface. They are used to detect and measure air or liquid pressure for applications like meteorology, altimeters, automotive, and medical applications.
Photoelectric Cells:
Photoelectric cells are active transducers which convert light into electricity. They are used in applications such as optical communications and control systems.
Passive Transducers
Passive transducers are devices that use an external force or energy source to convert energy from one form to another. They are used to measure physical quantities such as temperature, pressure, sound, and light without using an external power supply. Some of the most common passive transducers include thermistors, piezoelectric sensors, and microphones.
Examples of Passive Transducers
Thermistors: Thermistors are temperature-sensitive devices that convert temperature into an electrical signal without using an external power source. They are used to measure temperatures in the range -200 degrees Celsius to 400 degrees Celsius in a wide range of products such as computers, communication and radio systems, and automotive systems.
Piezoelectric sensors: Piezoelectric sensors are devices that convert mechanical vibrations into an electrical signal. They are used in applications such as vibration monitoring and medical imaging systems.
Microphones: Microphones are devices that convert sound into an electrical signal without using an external power source. They are used in audio systems, recording studios, and communication systems.
Conclusion
Transducers are devices that convert energy from one form to another. They are used in physics to measure physical properties such as pressure, light, heat, and sound. Transducers can be divided into two main types; active and passive transducers. Active transducers require an external power source to convert energy while passive transducers are self-powered devices. Examples of active and passive transducers include thermocouples, thermistors, pressure sensors, photoelectric cells, piezoelectric sensors, and microphones.
