Humidity sensors (hygrometers) measure and report the air’s relative humidity. They are used in homes, wine cellars, and working environments that that are so humid that they negatively impact working conditions. Humidity sensors are also used in vehicles, industrial HVAC systems, and meteorological stations to help in the predicting and reporting of weather conditions. How does a Humidity Sensor Work? Humidity sensors detect the relative humidity of the immediate environments in which they are placed. They measure both the moisture and temperature in the air and express relative humidity as Read More

The Seebeck Effect was first discovered in 1821. It describes the thermoelectric phenomenon that results when the temperature differences between dissimilar metals in a circuit are converted into electric current. This is one of three similar processes that relate to conductivity, temperature, and thermoelectricity that was discovered in the 1800s. The Thomson Effect was first written about in 1851 following the Peltier Effect explanation in 1834. Who Invented the Seebeck Effect? The effect is named after East Prussian scientist Thomas Johann Seebeck, who lived from 1770 to 1831. He first Read More

A permanent magnet (ferromagnet) is a material that produces a magnetic field. Permanent magnets are made from ferromagnetic materials, such as iron, and are created when the material is placed inside of a magnetic field. When the magnetic field is removed, the object remains magnetized. Permanent magnets have a permanent magnetic field and do not turn on and off like electromagnets do. Permanent magnets are the oldest type and are still used for a wide variety of applications today. How Permanent Magnets Work Permanent magnetization of a material involves its Read More

Solid mechanics defines torsion as the twisting of an object as a result of applied torque. Torsional vibration can be broadly described as the angular vibration of any object. It can be defined specifically as the periodic motion corresponding to a shaft, where the shaft is twisted about its axis, alternating from one direction to the other. Where does Torsional Vibration Occur? Torsional vibration is commonly a concern in large power transmission systems that incorporate shafts or couplings. In such environments, uncontrolled torsional vibration can cause transmission failure. An ideal Read More

An ultrasonic nebulizer is a small, portable device that uses ultrasonic sound waves to break liquid particles down into a fog so that they can be inhaled easily. Patients who have asthma, COPD, pneumonia, chronic bronchitis, emphysema, or other chronic conditions, most often use them for medicinal purposes. While other devices can deliver the medicine in a mist form, ultrasonic nebulizers provide a fog of medicine that has much smaller particles and can travel much deeper into the patient’s lungs, resulting in much faster relief. How does an Ultrasonic Nebulizer Read More

A superconductor is a substance which conducts an electric current with zero resistance. Superconduction is a phase state (like the liquid and solid states of the water); as such, it depends on the temperature among other variables. The temperature where the transition takes place is the critical temperature (Tc). In 1911, H. Kammerlingh Onnes discovered superconductivity working over mercury. Superconductors are classified as Type I or Type II depending on their transition behavior. In Type I, resistance falls to zero abruptly when Tc is achieved; Type II superconductors hold a Read More

The Venturi effect is the phenomenon that occurs when a fluid that is flowing through a pipe is forced through a narrow section, resulting in a pressure decrease and a velocity increase. The effect is mathematically described through the Bernoulli equation and can be observed in both nature and industry. Many industry applications rely on this effect as they need to be able to predict a fluid’s reaction when flowing through constricted piping. How does the Venturi Effect Work? The Venturi effect is similar to a jet effect, which is Read More

Magnetic bearings use magnetic force to support machine parts without there being any physical contact between the supporting mechanism and the device. The bearings’ magnetic force lifts the supported piece of machinery, permitting it to move while suspended in the air. Unlike traditional bearings, no friction is experienced, which results in significant savings and reduction in maintenance. Magnetic bearings have replaced traditional bearing types such as the ball bearing. How do Magnetic Bearings Work? Magnetic bearings are similar to traditional bearings in that they support machinery designed to rotate. Unlike Read More

Strain gauges measure the amount of stress or strain placed on an object. Arthur C. Ruge and Edward E. Simmons invented them in 1938. The most common type of strain gauge in use today consists of an insulating, flexible backing that supports a metallic foil pattern. The gauge is placed on the object with an adhesive. As the object comes under strain or gets deformed, the foil deforms and causes the electrical resistance to change. The change in resistance is then measured with a Wheatstone bridge. How does a Strain Read More

A linear actuator is a mechanical device that makes a linear motion, usually via a hydraulic pump or electromagnetic gear. Other forces can be used to create linear motion. The different types of linear actuators include screw, wheel and axle, cam, hydraulic pump, pneumatic, piezoelectric, and electro-mechanical. Linear motors, wax motors, and telescoping linear actuators can also produce linear motion. How a Linear Actuator Works While all linear actuators depend on an external, non-linear force to drive a piston back and forth, different types of linear actuators work in different Read More