Question

Electronic.. Super Position>>>

Answer 1

this circuit i already remove S/C =30V...
How can i calculate I1 here>>

Answer 2

Since the current going through 40 resister is, 6-I_1
$$V=IR$$
to $$40\Omega$$
$$V_a=(6-I_1)40\qquad (1)$$

current going through 20 resister is 5I_1
$$V=IR$$ to 10, 20 series cct,
$$V_a=(V_a-V_b)+(V_b-0)\\
V_a=10I_1+5I_1\times20=110I_1\qquad (2)$$
from (1) and (2)
$$(6-I_1)40=110I_1$$ find I_1

Answer 3

The Basic concept of the "Super Position Method" is to analyze a circuit,One source at a time.
Using the Superposition method,we remove all the (independent) source,except one, and analyze the circuit for that one.