A: the period of the wave
b: frequency of the wave

Period of the wave:

Frequency of the wave:

Explanation:

Period of the wave:To calculate the period of a wave from a displacement vs time graph we identify the amount of time it takes for one cycle to be completed. According to the graph, 1 cycle is completed in 0.4 seconds, so:

Frequency of the wave: To find frequency we simply calculate the inverse of the period because we know the relationship or

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.