A charge of eight-tenths of a coulomb (0.8 C) passes a point in 4 s. Using Q = I * t, what is the current in amperes through the conductor?

Introduction / Context:
Current is the rate of flow of electric charge. Whenever you know how much charge moves through a point and how long it takes, you can compute current using the fundamental relationship connecting these quantities. This problem reinforces the essential formula used throughout circuit analysis and instrumentation.

Given Data / Assumptions:

• Total charge Q = 0.8 C (eight-tenths coulomb).
• Time interval t = 4 s.
• Steady average current over the interval is implied.

Concept / Approach:

Use the definition of current: I = Q / t. Ensure units are SI: coulombs (C) for charge and seconds (s) for time. The result will be in amperes (A). Convert or simplify units only after computing the numeric value to avoid mistakes.

Step-by-Step Solution:

Verification / Alternative check:

Check order of magnitude: If 1 C in 1 s is 1 A, then 0.8 C in 4 s is less than that, so a value of 0.2 A makes intuitive sense. Another check: 0.2 A * 4 s = 0.8 C, which matches the given charge.

Why Other Options Are Wrong:

1.6 A and 2 A are too large for the given Q and t. 16 A is off by two orders of magnitude. 200 mA is a correct alternative expression but the question asks explicitly for amperes; 0.2 A is the precise amperes value.

Common Pitfalls:

Mixing milliseconds or microcoulombs without proper conversion, and confusing average with instantaneous current when the question clearly uses average over 4 s.

Final Answer:

0.2 A