The purpose of the solenoid simulation is to let the user explore the magnetic field inside and surrounding a solenoid. A complete worksheet is available to guide students in this exploration. Note the following:
- B-field strength is proportional to the current in the solenoid (I amps), and the number of turns per meter (NTPM) in the solenoid coil. The exact formula for a long solenoid is B = μ 0 I NTPM , where μ 0 = 4 π × 10 -7 .
- The B-field strength is proportional to the spatial density of the B-lines: that is, a lot of lines close together means a strong B-field
- The B-field is strong and very uniform inside the solenoid, and very weak outside.
- The direction of the solenoid field is determined by the “Right-Hand-Rule” and the solenoid produces North and South poles similar to a magnet.
Student Worksheet Downloadable Word Doc
We used the following word document as a lab procedure in the PHY112 class. However, it can be used with more advanced or engineering-level classes, because the concepts are significant. Document:
Points for Discussion
- Explain why the |B| at the end of a long solenoid is very close to half the B-field magnitude inside the solenoid?
- The solenoid produces a uniform magnetic field which is very strong inside the solenoid. How is this analogous to the capacitor and the electric field?
- There is much similarity between B-fields produced by a bar magnet and a solenoid. Is there an underlying similarity between magnets and solenoids that would explain this similarity?
- Do adjacent turns in the solenoid coil attract one another or repel?