LR Circuit Analysis: Calculating Current and Gradient (0-0.6 seconds)

[will.i.am2]

A coil connected across a d.c. supply will cause a spark to occur across a switch when turned off. The current flowing in the circuit at this moment is given by the equation i = IetR/L amps. Where I is the maximum circuit current, R the resistance of the coil and L the inductance of the coil.

(a) For a coil of resistance = 10Ω and Inductance 1.2 henrys through which the maximum current flowing was 5 amps, plot the graph for values of t between 0 and 0.6 seconds.
please refer to attached images.

(b)From the graph determine its gradient at t = 0.2 seconds.
26/0.2 = 130?
please refer to attached graph.

(c) Using calculus determine the gradient of the curve and from it the actual gradient when t = 0.2 seconds.
please refer to attached images.

So, any help would be appreciated.
thanks

****work is attached in form of images please don't remove it this time*****

 

[spaderdabomb]

Remember when taking the derivative of an exponential, you just get an exponential with some constants out front. That might help in drawing your graph =)

 

[Mark44]

Your derivative in part c is incorrect, as it was in the other problem you posted.

What is this derivative?
$$\frac{d}{dt}e^{tR/L}$$

BTW, it's reasonable to post images of tables and graphs, but you should post the work you did right here in the text pane, not as an image.

****work is attached in form of images please don't remove it this time*****

If you're referring to your post for the CR problem, the images are still there. No one removed them.