The effect of closing the key K in the circuit shown in the figure above would be to?
-
A.
increase the current by 0.4A -
B.
reduce the current by 0.4A -
C.
increase the current by 0.6A -
D.
reduce the current by 0.6A
Correct Answer: Option A
Explanation
When K is open. Total Resistance = 8 + 2 = 10(Omega)
1 = (frac{V}{Omega}) = (frac{6v}{Omega}) = 0.6A
Where K is closed, (frac{1}{8} + frac{1}{8} = frac{1}{Omega})
(frac{2}{8} = frac{1}{Omega})
(Omega) = (frac{8}{2}) = 4(Omega)
(Omega) = (frac{8}{2}) = 4(Omega)
4(Omega) in series with 2(Omega)= 6(Omega)
1 = (frac{V}{Omega}) = (frac{6}{6}) = 1A
1 – 0.6A = 0.4A increase
There is an explanation video available below.