Question

Difference in ammeter readings is

• A. $1A$
• B. $0A$
• C. $2A$
• D. $4A$

Answer 1

The correct option is B $0A$

The circuit can be reduced, step by step, to a single equivalent resistance. The 8 ohm and the 8 ohm are connected in parallel , and so they can be replaced by an equivalent resistor Rp of 4 ohms, using the below equation.
$Rp=\frac{(8\times 8)}{(8+8)}=4ohms$
This resistor is connected in series with the 4 ohm resistor R1. The total resistance Rt of the circuit is then
Rt =R1+Rp=4+4 = 8 ohms.
Since the 4 ohm and the 4 ohm are connected in series, they have the same current I1, which must be equal to the current of the battery. Using Ohms law we get,
$I=\frac{V}{R}=\frac{8}{8}=1A$.
Hence, the current flowing through the resistor R1 (4 ohms) is 1A.
The current flowing through a serially connected circuit, remains constant throughout and so there will not be any changes in the ammeter reading irrespective of the place where it is connected.