A circuit is set up as shown in the diagram above. When the key is closed, the ammeter reading will be
-
A.
6A -
B.
4A -
C.
2A -
D.
1A
Correct Answer: Option C
Explanation
The resistors are connected both in parallel and series. To calculate the total resistance, we have:
For the parallel connection: (frac{1}{R} = frac{1}{1} + frac{1}{1})
(frac{1}{R} = 2 implies R = 0.5Omega)
For the series connection: (R_{total} = (1 + 0.5)Omega = 1.5Omega)
Recall, (V=IR)
(3 = 1.5I implies I = frac{3}{1.5} =2A)