Explain the principle of working of lvdt

1. 
   Explain the principle of working of LVDT.
   

LVDT it is Linear Variable Differential Transformer. It is an important type of inductive transducer. The working of LVDT is based on the principle of Faraday’s law of electromagnetic induction that states that “the net induced emf in the circuit is directly proportional to the rate of change of magnetic flux across the circuit, and the magnetic flux of the coil wounded with wires can be changed by moving a bar magnet through the coil.

2. 
   Describe the working of RVDT with a neat sketch
   

The primary winding is excited by an alternating current source; it produces an alternating magnetic field which in turn induces alternating current voltages in the two secondary windings. A movable soft iron core is placed inside the former. The displacement to be measured by is applied to the arm attached to the soft iron core. The core is made of high permeability, nickel iron which is hydrogen annelid. This gives low harmonics, low null voltage & a high sensitivity. This is slotted longitudinally to reduce eddy current losses. The assembly is placed in stainless steel housing and the end lids provide electrostatic and electromagnetic shield.

3. 
   List the applications of potentiometer sensor in/around your home and office/university
   

A potentiometer sensor is used to sense motion, either rotary or linear.

1. 
   Automobiles use potentiometer sensors to detect, among other things, the position of the accelerator pedal and the rotational position of the steering wheel.
   
2. 
   Light dimmers use a potentiometer sensor to set the brightness.
   
3. 
   Electronic gaming devices use potentiometer sensors in the human interfaces for the game.
   

4. 
   To detect non-conducting metallic objects which sensor would be useful?
   

Optoelectrics. Photocells will detect anything that will break the projected beam or reflect the beam back to the integrated receiver. These can work at great distances, so are very useful. Less common are sonar types that project sound waves at a target, then process the reflected signal to provide a 0–5 volt or 4–20 milliamp analog signal for interpretation by the host machine.

5.