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fisher garry
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I have a problem with the derivation above I don't get how
Can someone derive this and illustrate this visually for example by using Figure 2 or using another drawing?
fisher garry said:well it is not from a textbook it is a document I recieved. Unfortunately I am a bit lost from
View attachment 254268
Angles and infinitesimals - ugh.fisher garry said:View attachment 254289
I have tried to illustrate my problem in the drawing above. Since ##r d\theta## is normal to the radius r and approximately linear since it is a short part of the bowlength the angle between dx and ##r d\theta## should be the same as the angle between r and x that makes cosinus. But what if the fraction ##\frac{r d\theta}{dx}## and the ##\frac{r }{x}## is not the same? We don't know the length of ##r d\theta## measured up to r and the length of dx measured up to x?
fisher garry said:View attachment 254289
I have tried to illustrate my problem in the drawing above. Since ##r d\theta## is normal to the radius r and approximately linear since it is a short part of the bowlength the angle between dx and ##r d\theta## should be the same as the angle between r and x that makes cosinus. But what if the fraction ##\frac{r d\theta}{dx}## and the ##\frac{r }{x}## is not the same? We don't know the length of ##r d\theta## measured up to r and the length of dx measured up to x?
fisher garry said:@fisher garry: can you please let us know which book you referred for above relation in your picture posted?
A solenoid is a coil of wire that is tightly wound in a helix shape. It is commonly used in electronic devices to create a magnetic field.
A magnetic field is created inside a solenoid when an electric current flows through the wire. The flow of electrons generates a magnetic field that is perpendicular to the direction of the current.
The strength of the magnetic field inside a solenoid is affected by the number of turns in the coil, the current flowing through the wire, and the material of the core (if present). Increasing any of these factors will result in a stronger magnetic field.
Yes, the direction of the magnetic field inside a solenoid is determined by the direction of the current. If the current is flowing in a clockwise direction, the magnetic field will be in a counterclockwise direction, and vice versa.
Yes, the magnetic field inside a solenoid can be turned on and off by controlling the flow of current through the wire. When the current is turned off, the magnetic field will also dissipate.