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When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$, where $\epsilon$ is the emf.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker for a given $\epsilon$ and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet (the drag force $F_d$ is also proportional to the velocity). If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?

When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$, where $\epsilon$ is the emf.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker for a given $\epsilon$ and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet (the drag force $F_d$ is also proportional to the velocity). If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?

Note: a terminal velocity will be reached in both cases. The terminal velocity for aluminium tube is higher than the terminal velocity for the copper tube.

When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet (the drag force $F_d$ is also proportional to the velocity). If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?

When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$, where $\epsilon$ is the emf.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker for a given $\epsilon$ and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet (the drag force $F_d$ is also proportional to the velocity). If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?

When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet. If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?

When you drop a magnet in a tube, the magnet is slowed down by induced Eddy currents due to the change in flux (repulsion from below and attraction from above).

We know that $\epsilon = -\frac{d\Phi}{dt}= IR$.

We know that if you use an aluminium tube instead of a copper tube (with the exact same dimensions), then the magnet will fall faster through the aluminium tube than the copper tube, because the aluminium tube has a higher resistance than the copper tube, thus the induced Eddy currents are weaker and the effect is weaker, so the magnets will fall faster.

I understand this explanation, but at the same time, if the magnet falls faster, then the emf is greater right? Since the emf here is proportional to the velocity of the magnet (the drag force $F_d$ is also proportional to the velocity). If the magnet falls faster, then the flux change is greater and thus the emf is greater. So why doesn't a greater emf compensate for the greater resistance? Why does the magnet still fall faster through the aluminium tube than the copper tube?