A current of 1.0 A is drawn by a filament of an electric bulb for 10 minutes. The amount of electric charge that flows through the circuit is
- A.0.1 C
- B.10 C
- C.600 C
- D.800 C
Correct answer
Explanation
The correct answer is C, 600 C. Charge equals current multiplied by time, and 1.0 A for 600 seconds gives 600 coulombs.
Electric current is the rate of flow of charge, so I = Q ÷ t, or Q = I × t. Time must be in seconds: 10 minutes is 10 × 60 = 600 seconds. So Q = 1.0 A × 600 s = 600 C. One ampere means one coulomb of charge passes a point in the circuit every second, and one coulomb is the charge of about 6.25 × 10¹⁸ electrons.
A is wrong because 0.1 C would come from dividing the current by the time in minutes, which has no physical meaning.
B is wrong because 10 C uses the time in minutes instead of converting it to seconds.
D is wrong because 800 C does not match 1.0 A for 600 seconds; it would need a longer time or a larger current.
Exam tip: Q = I × t with time in seconds; 1 ampere = 1 coulomb per second.
Practice Questions
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