2. You are measuring the current in a circuit that is operated on an 18 V battery. The ammeter reads 40 mA. Later you notice the current has dropped to 20 mA. How much has the voltage changed?
A. 18 V
B. 0 V
C. 9 V
D. 900 mV
2. You are measuring the current in a circuit that is operated on an 18 V battery. The ammeter reads 40 mA. Later you notice the current has dropped to 20 mA. How much has the voltage changed?
A. 18 V
B. 0 V
C. 9 V
D. 900 mV