Which of the these devices is used to measure the value of current in a given circuit?

Options

A. Ammeter
B. Electrode
C. Electrolytes
D. Galvanic cell

Answer

To determine which device is used to measure the value of current in a given circuit, we can analyze the options provided: ammeter, electrolytes, and galvanic cells.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Ammeter**: This is a device specifically designed to measure the electric current flowing through a circuit.
- **Electrolytes**: These are substances that produce an electrically conducting solution when dissolved in water. They do not measure current.
- **Galvanic Cells**: These are devices that convert chemical energy into electrical energy. They also do not measure current.

2. **Analyzing the Ammeter**:
- An ammeter is connected in series with the circuit to measure the current. It provides a direct reading of the current flowing through the circuit.

3. **Conclusion**:
- Since the ammeter is specifically designed for measuring current, it is the correct answer. The other two options (electrolytes and galvanic cells) do not serve this purpose.

### Final Answer:
The device used to measure the value of current in a given circuit is the **ammeter**.

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