“Whenever the magnetic flux linked with a circuit changes , an e.m.f induced in it”
” Whenever the a conductor cuts magnetic flux an e.m.f is induced in that conductor.“
The magnitude of the induced e.m.f is equal to the rate of change of flux – linkages.
Induced E . M . F at any instant. E= N dǿ/dt Volts
where N – number of turns in the coil.
dǿ/dt – rate of change of flux.
The lenz’s law states that the currents which are induced due to electromagnetic induction are in such a direction as to oppose the cause produce them. This law gives the direction of the induced current
Stretch out the right hand with first finger and the thumb mutually perpendicular to each other . If the first finger points in the direction of flux and thumb in the direction of motion of the generator, then the middle finger will point in the direction of the induced e. m. f.
Stretch out the left hand with first finger, middle finger and thumb at right angles to one another. If the first finger points in the direction of magnetic field ,middle finger points in the direction of current .then the thumb will points in the direction of the mechanical force of the conductor
Force ,f=Bil Newtons
“The Kcl states that in any electrical network the algebraic sum of all currents meeting
at any node equals zero at any instant of time”
Fig:kirchhoff’s current law
Apply KCL to this figure.Current directed away from the node are taken as postive and the currents dorected towards nodes are taken as negative the current equation of the code is
“The KVL states that in any electric network, the algebraic sum of voltage drop of all braches
forming a closed path (called loop) equal zero at any instant of time”.
Fig:kirchhoff’s Voltage law
The voltage drop in allop taken postive and voltage rises are taken as negative while writing KVL eguation
- Basic Electrical Engineering book M A COLLEGE OF ENGINEERING KOTHAMANGALAM
- Fundamentals of Electrical Engineering