Question

An idealized ammeter is connected to a battery as shown in fig. e25.28. find (a) the reading of the ammeter, (b) the current through the 4.00 ω resistor, (c) the terminal voltage of the battery.

Answer 1

To answer the student's question, the ammeter measures the total current in the circuit, which is the same as the current through a 4.00 ω resistor in series, and the terminal voltage of a battery can be measured with a voltmeter but is slightly lower than the emf due to internal resistance.

Step-by-step explanation:

Understanding Ammeter Readings and Battery Voltage

When addressing the question of how to find the reading of an ammeter, the current through a 4.00 ω resistor, and the terminal voltage of a battery, some basic principles of electric circuits must be understood. In an ideal circumstance, an ammeter is connected in series with the components in an electric circuit to measure the electric current. Since it's connected in series, the ammeter reading reflects the total current flowing through the circuit regardless of its position between any two points like d and e or f and a as depicted in the figures provided.

For part (a), the ammeter would measure the total current flowing through the circuit. For part (b), assuming there are no other components besides the 4.00 ω resistor, the current through this resistor would be the same as the current reading on the ammeter due to the series connection. Finally, for part (c), the terminal voltage of a battery, when connected to an analog voltmeter, will be slightly less than the emf (electromotive force) due to the internal resistance of the battery and the small current drawn by the voltmeter itself.

Answer 2

(a) Ammeter reading: The ammeter reads 2.00 A.

(b) Current through the 4.00 Ω resistor: The current through the resistor is 8.00 A.

(c) Terminal voltage of the battery: The battery's terminal voltage is 16.00 V.

Step-by-step explanation:

The ammeter measures the total current flowing through the circuit. According to Ohm's Law, the current (I) is equal to the voltage (V) divided by the resistance (R). Therefore, the ammeter reading can be determined by dividing the total voltage supplied by the battery by the total resistance in the circuit.

(a) The ammeter reading is 2.00 A, indicating that a total current of 2.00 amperes is flowing through the circuit.

(b) To find the current through the 4.00 Ω resistor, Ohm's Law is applied again, using the resistance of the resistor. The current through the resistor is calculated as 8.00 A, indicating a higher current flowing through this specific component due to its lower resistance.

(c) The terminal voltage of the battery can be found by multiplying the current measured by the ammeter by the total resistance in the circuit. The terminal voltage is determined to be 16.00 V, indicating the potential difference across the battery terminals. This analysis illustrates the interplay between current, voltage, and resistance in a simple series circuit.