. A study of wireless telegraphy and wireless telephony . e force of thecondenser has become zero, since an active electromotive forceis induced in the induction coil by the change in its magnetismand does not allow the current to come to zero value process charges the condenser oppositely to its originalcharge and when the current in this direction ceases, the backelectromotive force of the condenser starts the current in thereverse direction. This process then repeats again and again,until the oscillations reduce to zero, the rapidity of oscilla-tions depending upon the values
. A study of wireless telegraphy and wireless telephony . e force of thecondenser has become zero, since an active electromotive forceis induced in the induction coil by the change in its magnetismand does not allow the current to come to zero value process charges the condenser oppositely to its originalcharge and when the current in this direction ceases, the backelectromotive force of the condenser starts the current in thereverse direction. This process then repeats again and again,until the oscillations reduce to zero, the rapidity of oscilla-tions depending upon the values of self inductance, capacityand resistance. Due to tne presence of some resistance in thecircuit, the electrical energy is gradually dissipated into heat(as in the case of the spring) and hence the maximum of thecurrent at each oscillation becomes less and less until all ofthe electrical energy originally stored in the condenser hasbeen transformed into heat energy. This decrease of amplitudeof the oscillation is known as damping and is shown by Fig. Previous to Lord Kelvins researches oscillations had beenobserved, but the circuit requirements for their productionwere not clearly understood. it was shown by Lord Kelvin mathe-matically, that the discharge takes place in the oscillatory 6. manner just described only for such values of resistance in thecircuit as will make R2<4L/C. If, however, this equation is notsatisfied, then the discharge is unidirectional as shown by hismathematical developments, results of which are given below:If we let V0= the initial difference of potential,C = the capacity,L s the inductance,and R = the resistance, then,CASE I. When R24L/C. 1 = A/r2- 4LV C J, T2 - e t Tl in which To = 2LC arid T1= -^gLC^ = RC+ ~AR2C2-4LC This is the general case of non-oscillatory discharge. The expresssion for the critical case, in which the discharge is just non-oscilstudyofwirelesst00elea
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecttheses, bookyear1915
