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The general formula to calculate the EMF in a loop of wire due to a change in magnetic flux is:
$$\mathcal E = - \frac{\mathrm{d} \Phi_B}{\mathrm{d}t}$$

This means that as the magnetic flux through a loop of wire (which is often the result of a current in another wire nearby) decreases, the EMF in the loop of wire will increase, which will in turn result in a higher current. Maybe I am not thinking about it in the correct way, but it seems counterintuitive that a decrease in something that causes current to flow will result in an increase in the flow of current.

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  • $\begingroup$ Why? Well, the theory was crafted to reproduce experiments, and if you do the experiment you'll verify the effect. But then, appealing to the theory for an explanation is circular reasoning. $\endgroup$
    – John Doty
    Apr 26, 2022 at 21:31
  • $\begingroup$ > "decrease in something that causes current to flow" -- here is the misconception. Magnetic flux does not cause current to flow. It is the changing magnetic flux in time is associated with EMF, not just the presence of magnetic flux. $\endgroup$ Apr 26, 2022 at 22:48

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There is an emf associated with a decrease of the magnetic flux according to the Maxwell Faraday equation. It can be seen when a DC circuit is opened, separating a wire from the terminal. If the circuit is inductive, instead of purely resistive, the spark asssociated with the disconnection is bigger.

The energy stored in the coil is dissipated by this emf (and current) when the circuit is opened.

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Although the equation you provided is correct your conclusion is not.

The equation relates the EMF to the rate of change of flux with time. Can be either positive or negative, it doesn't matter, The polarity direction of the induced EMF is signified by the minus sign in the equation thus the Lenz law and has nothing to do with reduction of the flux.

The more abrupt are the changes in flux the larger EMF is produced that is a +2 Wb units flux change within $1s$ will generate the same absolute value of EMF as -4 Wb flux change in $2s$.

Imagine the self-induced EMF in a coil as being similar to inertia of mass that resists any sudden acceleration or deceleration.

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It is because in nature when an EM field, whether increasing or decreasing, changes, another field is produced (induced) to resist the change. When the magnetic flux is decreased, the EMF increases to produce a current in the wire so that the induced magnetic field of this current opposes the reduction in the main/external magnetic field.

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