What Attracts a Solenoid's Northern End: A Bar Magnet's Polarities?

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The northern end of a solenoid attracts the southern end of a bar magnet, confirming that the northern side of the solenoid is indeed a north pole. The discussion also clarifies that kinetic energy (KE) is not equal to potential energy (PE), as KE is defined as 1/2 mv^2. Electric potential is described as the work done on a unit positive charge when moving to a point where potential is zero, with potential energy expressed as PE=qV. The work done by an electric field when a charge moves from a potential V to zero is W=qV, and the unit of potential is volts (V). Overall, the relationship between these concepts highlights the distinctions between energy forms and electric potential.
Eleventh_Hour
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It's a small question, really. For solenoids, if I have a 'northern' end, what part of a bar magnet would be attracted to it? Is the Northern side actually a north pole?

Also, is KE = PE = Work = qV ~ where V is voltage / emf?
 
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The northern end of a solenoid attracts the south end of a bar magnet.

It is the Earth, which has its south pole as a magnet at the North Magnetic Pole.

As your other question, KE =1/2 mv^2 is the kinetic energy and it is not equal to the potential energy PE. The electric potential at a point is the work done on a unit positive charge when it moves from that point to somewhere where the potential is defined zero. The potential energy of a charge q is PE=qV. The work of the electric field when the charge moves from a point at V potential to 0 potential is W = qV. The unit of potential is volt (V), that of work is joule (J).
The emf of a voltage source is the potential difference between its terminals when no load is connected.

ehild
 
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