How does surface texture affect friction

The rougher a surface is, the more friction it can create.

Explanation:

The rougher a surface is, the more "holes" are on the edge which means things can get caught on in because multiple holes can catch each other.

96.77 amp

explanation:

rl = 250/100 = 2.5 ohms.

egl = 250 + (100 × 0.1) + 2 = 262 v.

at 700 r.p.m., eg2 = 262 × 700/1000 = 183.4 v.

if ia is the new current, then eg2 - 2 - (ia × 0.1) = 2.5 ia

which means this will give ia = 96.77 amp.