I have a question about the relationship between Faraday's and Lenz's law from a graph of the emf of Faraday's Law compared to the voltage in a coil. My question is whether or not this graph supports Lenz's law. Also, is it possible to determine from this graph if the direction of the induced current is going in the expected direction when the magnetic field is increasing? 
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1$\begingroup$ How did you obtain this data? $\endgroup$– BRTApr 18, 2017 at 22:52
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1$\begingroup$ Without a diagram showing the physical setup used to collect your data, your question probably cannot be answered. $\endgroup$– David WhiteApr 19, 2017 at 0:45
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$\begingroup$ The data was obtained using a rigid pendulum with a coil at its end swings through a horseshoe magnet. A resistive load is connected across the coil and the induced voltage is recorded using a Voltage Sensor. Faraday's Law is used to estimate the magnetic field of the magnet from the maximum induced voltage. Also, the direction of the induced voltage as the coil enters and leaves the magnetic field is examined and analyzed using Lenz' Law. Is this sufficient information to answer the question? $\endgroup$– IwasykiwApr 19, 2017 at 1:05
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$\begingroup$ This question does not make sense. If a resistor is in series with the coil, and $V$ is voltage across the resistor, then current is proportional to $V$ and EMF, given by $-LdI/dt$, should behave as derivative of $V(t)$. But there is is no trace of this in the graph, the EMF seems to copy the function $V(t)$. How did you determine EMF? $\endgroup$– Ján LalinskýJun 28, 2018 at 8:34
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You could say something about Lenz law if you had measured the current too (positive or negative). You should measure EMF and current, then cross-plot it carefully because of the signs involved.
If you only calculated V and measured EMF you can't 'prove' Lenz's law because you've used it implicitly (the minus sign at Faraday's law from Maxwell's equations)
