You are given following current-time graph from two different sources,

(i) Name the type of current in two cases.
(ii) Identify any one source for each type of these currents.
(iii) What is the frequency of current in case source II in India?
(iv) Use above graph to write two differences between the currents in the two cases.

Explanation

(i) Some I represents direct current (DC) whereas source II represents alternating current (AC).
(ii) Source I may be a dry cell or a Voltaic cell and Source II is an AC Generator.
(iii) The period (T) of AC (Source II) is `0*03s-0*01s=0*02s`. Thus, the frequency of AC, i.e., `v=1/T=(0)/(0*02s)=50Hz`.
(iv) (a) The magnetude of DC remains the constant whereas that of AC keeps on changing.
(b) The direction of DC remains the same whereas that of AC keeps on changing.