Magnetic effect of an electric current

Electrolysis of copper sulphate solution using copper electrodes

Electrolysis of copper sulphate solution using copper electrodes When copper electrodes are used the action at the cathode is exactly the same as with platinum or carbon electrodes. Cu2+ ions are discharged and deposited on the cathode. At the anode, however, copper ions go into solution in preference to the discharge of either OH – or S042 – …

Electrolysis of copper sulphate solution using copper electrodes Read More »

Magnetic flux due to current in two vertical parallel wires

Magnetic flux due to current in two vertical parallel wires If two parallel wires are arranged side by side vertically and carry currents in the same direction the magnetic flux in a horizontal plane close to the wires is as shown in Fig. 36.16. A neutral point is formed between the wires, its exact position depending on the …

Magnetic flux due to current in two vertical parallel wires Read More »

Resultant magnetic flux in a horizontal plane due to the earth and the current in a long vertical wire

Resultant magnetic flux in a horizontal plane due to the earth and the current in a long vertical wire The iron-filings method described on page 420 to investigate the magnetic flux due to a current in a long straight wire gives information only about the strong field very close to the wire. In order to study the field …

Resultant magnetic flux in a horizontal plane due to the earth and the current in a long vertical wire Read More »

The telephone receiver (earpiece)

The telephone receiver (earpiece) The telephone receiver contains a U-shaped magnet formed by placing a short permanent bar magnet across the ends of two soft-iron bars (Fig. 36.14). This is placed so that it exerts a pull on a springy magnetic alloy diaphragm. Two solenoids are wound in opposite directions on the soft-iron bars. When a person speaks …

The telephone receiver (earpiece) Read More »

The solenoid switch (magnetic relay)

The solenoid switch (magnetic relay) The current required by the starter motor of a car is very high, and this requires very thick cable and a switch with heavy contacts. For convenience, a solenoid switch is used, the operation of which will be understood from Fig. 36.12. The starter switch, taking only a small current, is usually incorporated in …

The solenoid switch (magnetic relay) Read More »