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1. Homework Statement
When an aluminum ring is placed on ring launcher so that it surrounds the coil, it flies upward when a AC current is applied to the coil. This does not occur when the intact ring is replaced by a split ring (see below). Explain this in 3 sentences or less. Feel free to use as many diagrams and equations as you need in your explanation. [Warning: The standard explanation of this lacks any mention of an essential feature.]
2. Homework Equations
3. The Attempt at a Solution
This is my rationalization as to why this occurs:
When the ACcurrent was turned on, the emf generated in the Aluminum ring led to a current in it, which according to Lenz's Law, has to be in a direction such that its field cancels the one due to the ring launcher: so it is opposite in direction and since opposite currents repel, the ring flies off. When a split ring is used, since it is not a closed loop, there is no flux going through it is 0. Hence, there is no emf or current generated: so it does not fly off.
Did this go beyond the "standard explanation", as my Professor puts it? Or did I miss something "essential?" I have uploaded a picture of the figure (if it helps at all). I can only receive partial credit if my Professor isn't completely satisfied with the answer so if I'm missing something, I would greatly appreciate it if anyone could help steer me in the right direction. Thank you so much!
When an aluminum ring is placed on ring launcher so that it surrounds the coil, it flies upward when a AC current is applied to the coil. This does not occur when the intact ring is replaced by a split ring (see below). Explain this in 3 sentences or less. Feel free to use as many diagrams and equations as you need in your explanation. [Warning: The standard explanation of this lacks any mention of an essential feature.]
2. Homework Equations
3. The Attempt at a Solution
This is my rationalization as to why this occurs:
When the ACcurrent was turned on, the emf generated in the Aluminum ring led to a current in it, which according to Lenz's Law, has to be in a direction such that its field cancels the one due to the ring launcher: so it is opposite in direction and since opposite currents repel, the ring flies off. When a split ring is used, since it is not a closed loop, there is no flux going through it is 0. Hence, there is no emf or current generated: so it does not fly off.
Did this go beyond the "standard explanation", as my Professor puts it? Or did I miss something "essential?" I have uploaded a picture of the figure (if it helps at all). I can only receive partial credit if my Professor isn't completely satisfied with the answer so if I'm missing something, I would greatly appreciate it if anyone could help steer me in the right direction. Thank you so much!
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