Is the ammeter reading 2A and the power absorption 100W or did I calculate this incorrectly?
Electronic – Is this ammeter and power reading correct
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Best Answer
Because the ammeter's internal impedance can be assumed to be zero, there has to be 12 volts across the 25 ohm resistor. That means the power in the 25 ohm resistor is: -
$$\dfrac{12^2}{25} = 5.76\hspace{0.2cm}\text{watts}$$
And the current into the resistor is \$\dfrac{12}{25}\$ amps = 0.48 amps.
The rest of the current from the 2 amp source flows into the 12 volt source via the ammeter i.e. 1.52 amps.