If magnetic flux $\phi = (3t^2 - 2t + 5) \ Wb$,then what is the induced emf at $t = 2 \ s$?

(10 V) According to Faraday's law of electromagnetic induction,the induced emf $\varepsilon$ is given by $\varepsilon = -\frac{d\phi}{dt}$.
Given $\phi = 3t^2 - 2t + 5$.
Differentiating with respect to $t$,we get $\frac{d\phi}{dt} = \frac{d}{dt}(3t^2 - 2t + 5) = 6t - 2$.
The magnitude of induced emf is $|\varepsilon| = |6t - 2|$.
At $t = 2 \ s$,$|\varepsilon| = |6(2) - 2| = |12 - 2| = 10 \ V$.