Exam 2 Solutions
... B = µ0i / 2R , where R is the radius and i is the current. From the directions of the currents and the relation of the loop radius, the B = 0 condition gives 0 = I / 3+ I / 2 − I1 , where Il is the current in the innermost loop. This yields I1 = 5I / 6 = 12.5 A. 10. A long wire carries a 500 A curre ...
... B = µ0i / 2R , where R is the radius and i is the current. From the directions of the currents and the relation of the loop radius, the B = 0 condition gives 0 = I / 3+ I / 2 − I1 , where Il is the current in the innermost loop. This yields I1 = 5I / 6 = 12.5 A. 10. A long wire carries a 500 A curre ...
Physik-Quiz - Physikunterricht.at
... How can you magnetize a piece of steel? a) by placing it near a magnet. b) by rubbing it with one end of a magnet. c) by heating it. d) by placing it in a coil of wire and pass current through the coil. ...
... How can you magnetize a piece of steel? a) by placing it near a magnet. b) by rubbing it with one end of a magnet. c) by heating it. d) by placing it in a coil of wire and pass current through the coil. ...
Electromagnetic Induction and Waves
... Magnetic flux In order to calculate a changing magnetic field, or the changing field seen by a wire moving through a magnetic field, we need a new quantity, magnetic flux. A loop of wire, area A, in a magnetic field, B, at angle θ, is said to have a magnetic flux, Φ: ...
... Magnetic flux In order to calculate a changing magnetic field, or the changing field seen by a wire moving through a magnetic field, we need a new quantity, magnetic flux. A loop of wire, area A, in a magnetic field, B, at angle θ, is said to have a magnetic flux, Φ: ...
![1] How will you show the directive property of a magnet? Suspend a](http://s1.studyres.com/store/data/001625610_1-56f6c1434741143a0c22f345e56fb644-300x300.png)
Electromagnet
An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. The magnetic field disappears when the current is turned off. Electromagnets usually consist of a large number of closely spaced turns of wire that create the magnetic field. The wire turns are often wound around a magnetic core made from a ferromagnetic or ferrimagnetic material such as iron; the magnetic core concentrates the magnetic flux and makes a more powerful magnet.The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.Electromagnets are widely used as components of other electrical devices, such as motors, generators, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment. Electromagnets are also employed in industry for picking up and moving heavy iron objects such as scrap iron and steel.