Induction Machines. The simplest form of the induction machine is the electrophorus.

 In fact, a large induction machine may be considered a continuous electrophorus. Many forms of induction machines are in use. In the Toepler-Holtz machine there is a fixed glass disk called the field plate, having pasted upon the back side four tin-foil disks, T, connected two and two by strips of tin foil covered with large sectors of paper. These inductors correspond, one pair to the glass plate of an electrophorus (being charged positively), and the other to the ebonite plate of another electrophorus (charged negatively). In front of the field plate is a second glass disk, which rotates upon an axis. On the front face of this disk there are pasted, at equal intervals, six tin-foil disks, to the centers of which there are cemented metal buttons. These correspond to the brass disk of an electrophorus. A fixed rod, with a metal comb at each end, crosses diagonally from A to B in front of the movable plate, and fulfills the function of the finger that touches the electrophorus disk. The two kinds of electricity are taken off by collecting combs on opposite sides, connected with two rods which have at their outer ends insulating handles, K and K', and on the inner ends brass balls, the terminals between which the discharge takes place. A brighter spark may be obtained by connecting a Leyden jar to each terminal, as shown in the figure.

The machine is first charged by setting the rotating plate in motion and then sending a spark of + electricity from a charged glass rod to one of the inductors on the back of the stationary plate, for example, on the right-hand side in the figure. This induces a - charge in and near disk A on the rotating plate, and through the diagonally fixed rod a + charge is repelled to disk B. As the plate rotates, disk A is carried to the left, and the metal button on it is brought into contact with a small metal brush attached to C, an arm connected with the inductor on the left side of the field plate. A part of the - charge of disk A passes over to that inductor, the remainder is repelled by the - inductor into the collecting comb connected with K, and when this disk A reaches the position marked B, it is charged positively by the direct influence of the left-hand inductor combined with the indirect influence of the other inductor, as explained at the beginning. Meanwhile the original disk B has given up part of its + charge to the right-hand inductor through C", and the rest to the collecting comb connected with K', and at position A is receiving a - charge by induction, in the same way that the disk at B is receiving a + charge.

The terminals should be put in contact until a hissing sound shows that the machine is highly charged. When they are separated, a series of sparks will pass from one terminal to the other. Examine the two sides of the machine with a pith-ball electroscope to see which is + and which -. Discharge it, start over again, using a spark from a stick of sealing wax to charge the first inductor, and examine with pith-ball electroscope as before.

اخر الاخبار

اخبار العتبة العباسية المقدسة

المجمع العلمي للقرآن الكريم يصدر الكتاب الثاني من سلسلة يخشى

قسم الشعائر يكرّم أصحاب المواكب المشاركة في إحياء ذكرى شهادة السيدة الزهراء (عليها السلام)

جامعة العميد تستقبل طلبة المراحل الأولى المقبولين ضمن كلياتها للعام الدراسي الجديد

سماحة السيد الصافي يكرّم طلبة حفظ القرآن الكريم المتفوّقين ويؤكّد دور التدبّر في الهداية والتكامل

المزيد

الآخبار الصحية

طبيب يكشف تأثير برودة الشتاء على النوم

دون أن تعلم.. 10 عادات يومية تسرع شيخوخة جسمك

تقرير: النيكوتين خطر على القلب مهما كانت الطريقة

أيهما أفضل لصحتك.. زبدة الفول السوداني أم النوتيلا؟

المزيد

الآخبار التكنلوجية

السعودية تدشن أكبر نظام لتخزين الكهرباء بالبطاريات في العالم !

بأمر تنفيذي.. ترامب يؤكد هدف عودة الأميركيين إلى القمر في عام 2028

بعيدا عن البشر.. "قتال جوي في الفضاء" بين أميركا والصين

كشف مذهل في قاع "برمودا" !

المزيد

مواضيع ذات صلة

​Arc Lighting

Electric Welding

Electric Railways

The Incandescent Circuit

The Transmitter

The Telephone

Thermoelectric Currents

The Transmission of Electrical Energy

True Metal Filament Lamps

Telephone Line Circuit

The Inclosed Arc Lamp has

The Resistance of a Cell