Skip to main content

Lorentz force equation

 Lorentz Force Equation


 

The force experienced by current element in magnetic field is given as sum of force due to electric field and magnetic field. 

Force due to electric field:


A region is said to be characterized by an electric field if a particle of charge q moving with

a velocity v experiences a force Fe, independent of v. The force, Fe, is given by

             Fe = qE ---------------------------------------- (1.1)

lorentz-force

                  E is the electric field intensity. Measured in newtons per coulomb (N/C) or volts per meter.

Where volt is a newton-meter per coulomb. The line integral of E between two

points A and B in an electric field region gives voltage between A and B. It is the work per unit charge done by the field in the movement of the charge from A to B.

Force due to magnetic field:


If a charged particle experiences a force which depends on v, then the region is said

to be characterized by a magnetic field. The force, Fm, is given by

                    Fm=qv * B


where B is the magnetic flux density.

  • the units of B are newtons/coulomb meter per second or Volt seconds per square meter.

  • more commonly used units are Weber’s per square meter (Wb/m2) or Tesla (T), where a Weber is a volt-second.

  • The surface integral of B over a surface S is the magnetic flux (Wb) crossing the surface.

  • The magnitude of the force is qvBsinα, where α is the angle between v and B.


then force experienced by current element in magnetic field is given as sum of force due to electric field and magnetic field i.e. Fe+Fm

lorentz-eq

                  final equation is given as :                  


                                         F = Fe+Fm


                                         F= (qe) + (qv * B) = q (e + (v * B))

Labels:

Comments

Post a Comment

Popular posts from this blog

Transistor

Introduction: A transistor is a semiconductor device which is used to amplify the signals as well as in switching circuits. Generally, it consists of three terminals emitter(E), base(B) and collector(C) and two P-N junctions. It is one of the active components. It was invented by John Bardeen, William Shockley and Walter Brattain in 1948, in Bell Telephone Laboratories. Transistors are divided into different types depending on their construction and operation. Transistors are basically classified into two types; they are Bipolar Junction Transistors (BJT) and Field Effect Transistors (FET). The BJTs are again classified into NPN and PNP transistors. The FET transistors are classified into JFET and MOSFET. Junction FET transistors are classified into N-channel JFET and P-channel JFET depending on their function. MOSFET transistors are classified into Depletion mode and Enhancement mode. Again depletion and enhancement mode transistors are classified into N-channel JFET and P-channel. d...
2 comments
Read more

BJT (bipolar junction transistor)

A bipolar junction transistor is a three terminal semiconductor current controlled device with two P-N junctions. The three terminals are emitter(E), base(B) and collector(C). the emitter junction is heavily doped, base is less doped and made very thin and collector terminal is moderately doped. Collector has grater size than emitter and base terminal is thinner than both. (The thinner the base, the stronger the E-C electric field, and the larger the impact of a small current injected into the base. Explained clearly in active mode operation below) emitter terminal is moderate in size. A BJT has two types of transistors: NPN transistor PNP transistor NPN transistor : In an NPN transistor a p-type material is sandwiched between two n-type materials. [gallery ids="979,978" type="rectangular"] PNP transistor : In a PNP transistor a n-type material is sandwiched between two p-type materials. [gallery ids="989,990" type="rectangular"] Oper...
2 comments
Read more

P-N junction diode

A P-N junction diode is a basic diode. It is the combination of P-type and N-type semiconductor. symbol : P-N junction and potential barrier : A P-N junction is the basic building block of many semiconductor devices like diodes and transistors. P -n  junctions are formed by joining  n -type and  p -type semiconductor materials. Since the  n -type region has a high electron concentration and the  p -type a high hole concentration this difference in concentration creates density mismatch across junction which results to creation of potential barrier. The value of potential barrier v b  is 0.3 for germanium and 0.7 for silicon. Working : Forward bias: Application of positive charge at p-side pushes holes towards potential barrier and similarly negative charge at N-side pushes electrons towards barrier if input voltage is grater than potential barrier then electrons diffuse from the  n -type side to the p-type side. Similarly, holes flow by diffusion from the p-type side to the n-type side...
4 comments
Read more