Physics Question Electromagnetic induction

[darkpichu]

Anyone can help me answer this question, thanks!

 

[destined007]

Here:

 

[darkpichu]

Hello I cannot seem to understand this answer could you please explain me in more details?

Why is the first part of E-t graph negative while the last part is positive?

 

[destined007]

The current is increasing, ie, +ve so E will also increase but will in -ve area. The current is decreasing, ie, is -ve, so E will decrease but will be in +ve area.